abstruse
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C2 adjective /æbˈstruːs/

abstruse

難解
Meaning
Difficult to understand; obscure.
Example
The abstruse nature of the philosophical debate left many confused.
哲学的議論の難解な性質は多くの人々を困惑させた。
C2 noun /ˈækəlaɪt/

acolyte

Meaning
a follower or assistant, especially in a religious service or as a devoted supporter of a leader
Example
The senator arrived with a small group of acolytes who handled the press.
C2 noun /əˈspær.ə.ɡəs biːn/

Asparagus bean

アスパラガス豆
Meaning
a long, thin green vegetable pod that grows on vines; also known as yard-long bean
Example
The asparagus bean grows up to three feet long and is commonly used in Asian cooking.
アスパラガス豆は最大で三フィートの長さになり、アジア料理で一般的に使用されます。
C2 verb /əˈniːl/

anneal

熱処理で硬化する
Meaning
To heat and cool metal or glass to make it stronger or less brittle.
Example
The blacksmith annealed the steel to improve its durability.
鍛冶屋は鋼を熱処理してその耐久性を向上させました。
C2 adverb /əˈskæns/

askance

疑いの目で
Meaning
With suspicion, mistrust, or disapproval.
Example
She looked askance at his unusual proposal.
彼女は彼の異常な提案を疑いの目で見た。
C2 adjective /əˈbɪs.əl/

abyssal

深海の
Meaning
Related to or characteristic of the deep ocean, especially the zone below 4000 meters.
Example
Abyssal creatures survive in extreme pressure conditions.
アビサルクリーチャーは極端な圧力条件で生き残ります。
C2 noun /ˈæntɪfɒn/

antiphon

アンティフォン
Meaning
a short chant or verse sung responsively in Christian worship, typically sung before or after a psalm or canticle
Example
The choir sang the antiphon before beginning the main hymn.
合唱団は主の賛歌を始める前にアンティフォンを歌いました。
C2 noun /əˈfeɪ.ʒə/

aphasia

Meaning
a medical condition that causes loss of ability to speak or understand language
Example
After the stroke, she was diagnosed with aphasia.
C2 verb /əˈkuːtər/

accouter

装備する
Meaning
to equip or outfit, typically with military or ceremonial attire
Example
The soldiers were accoutered in full battle gear.
兵士たちは完全な戦闘装備を整えていた。
C2 noun /ˌær.əˈbesk/

arabesque

装飾的デザイン
Meaning
a complex, ornate design featuring intertwined flowing lines, often used in architecture or ballet poses
Example
The ceiling was decorated with delicate arabesque patterns.
天井は繊細なアラベスク模様で飾られていました。
C2 verb /ˈæmbl/

amble

ゆっくり歩く
Meaning
To walk at a slow, relaxed pace.
Example
They amble through the park on Sunday mornings.
彼らは日曜日の朝に公園をゆっくり歩いています。
C2 noun /ˌæs.əˈfet.ɪ.də/

Asafoetida

アサフェティダ
Meaning
a pungent spice derived from the resin of a plant, commonly used in Indian cooking
Example
A pinch of asafoetida adds a distinctive flavor to the lentil curry.
アサフェティダを少し加えると、レンズ豆カレーに独特の風味が加わります。
C2 noun (plural) /ˈɔːspɪsɪz/

auspices

後援
Meaning
Patronage, support, or guidance, often used in the phrase 'under the auspices of'.
Example
The conference was held under the auspices of the United Nations.
会議は国連の後援の下で行われました。
C2 noun /əˈkjuːtnəs/

acuteness

鋭敏さ；深刻さ
Meaning
sharpness of mind or senses; severity or intensity of a condition
Example
Her acuteness allowed her to notice details others missed.
彼女の鋭敏さは他の人が見逃した細部に気づかせた。
C2 noun /ˌæntɪˈtɒksɪn/

antitoxin

抗毒素
Meaning
A substance that neutralizes a specific toxin in the body.
Example
The doctor administered an antitoxin to counter the snake venom.
医師は蛇の毒を無効にするために抗毒素を投与しました。
C2 noun /əbˈdʌktər/

abductor

誘拐犯
Meaning
a person who kidnaps or forcibly takes someone away
Example
The police arrested the abductor after a nationwide search.
警察は長い捜索の後で誘拐犯を逮捕した。
C2 noun əˈdrɔɪt.nəs

adroitness

巧みさ
Meaning
Cleverness or skill, especially in using the hands or mind; skillful dexterity.
Example
His adroitness in negotiations secured the deal.
彼の交渉での巧みさが契約を成立させた。
C2 noun /ˈɪəri/ or /ˈɛəri/

aery

ワシの巣
Meaning
An eagle’s nest, or a lofty, airy dwelling.
Example
The eagle perched proudly near its aery high on the cliff.
鷲は崖の上にあるその巣の近くに誇らしげに止まった。
C2 noun /ˈɑːrtɪfɪs/

artifice

策略
Meaning
clever or cunning devices or tricks used to deceive others
Example
The politician's charm was nothing but artifice.
その政治家の魅力は単なる策略にすぎなかった。
C2 adjective /ˌæntɪˈθɛtɪkəl/

antithetical

対照的な
Meaning
Directly opposed or contrasted; mutually incompatible.
Example
His views were antithetical to the values of the organization.
彼の見解は組織の価値観と真逆でした。
C2 noun /ænˈtɪpəθi/

antipathy

アンチパシー
Meaning
a deep-seated feeling of dislike or aversion toward something or someone
Example
There was a mutual antipathy between the two rival companies.
二つの競争する企業の間に相互のアンチパシーがありました。
C2 verb /əˈvʌls/

avulse

引き裂く
Meaning
to tear away or separate forcibly, especially in medical or geological contexts
Example
The surgeon had to avulse the damaged tissue during the operation.
外科医は手術中に損傷した組織を引き裂かなければならなかった。
C2 noun /əˈsɜːrbəti/

acerbity

辛辣さ
Meaning
bitterness or sharpness of tone, manner, or taste
Example
The acerbity of his remarks left everyone silent.
彼の発言の辛辣さは、みんなを静かにさせた。
C2 adjective /eɪˈsɛptɪk/

aseptic

無菌
Meaning
Free from contamination caused by harmful microorganisms; sterile.
Example
Surgeons must work in an aseptic environment to prevent infection.
外科医は感染を防ぐために無菌環境で作業しなければならない。
C2 adjective /əˈbɔːrtɪv/

abortive

失敗した
Meaning
Failing to produce the intended result; unsuccessful.
Example
Their abortive attempt to climb the mountain ended in retreat.
彼らの山登りの試みは、撤退で終わった。
C2 noun /ˌækwəˈpɒnɪks/

aquaponics

アクアポニックス
Meaning
A system of aquaculture in which the waste produced by farmed fish or other aquatic animals supplies nutrients for plants grown hydroponically.
Example
Aquaponics efficiently utilizes water by integrating fish and plant farming.
アクアポニックスは魚と植物の農業を統合することによって水を効率的に利用します。
C2 noun /ˈeɪʒən siː bæs/

Asian sea bass

アジアスズキ
Meaning
a large predatory fish found in coastal waters and estuaries of the Indo-Pacific region, prized for its white meat
Example
Asian sea bass is highly valued in aquaculture for its fast growth.
アジアスズキは成長が早いため、養殖業で高く評価されています。
C2 verb /əˈɡriːv/

aggrieve

傷つける
Meaning
to cause distress or make someone feel resentful
Example
She felt aggrieved by the unfair decision.
彼女は不公平な決定に心を痛めていた。
C2 noun /ˈæn.dʒi.əʊ.plæs.ti/

angioplasty

血管を開くための医療手術で、心臓に血液を供給する血管が閉塞または狭窄している場合に行われます。
Meaning
A medical procedure to open blocked or narrowed blood vessels that supply blood to the heart.
Example
Angioplasty is now safer with robotic assistance.
ロボット支援で、アンジオプラスティは現在より安全です。
C2 verb /əˈlɪtəreɪt/

alliterate

頭韻を踏む
Meaning
to repeat the same consonant sound at the beginning of words in a phrase or sentence
Example
The poet often alliterates words to create rhythm.
詩人はしばしばリズムを作り出すために言葉をアリテレートします。
C2 noun /əˈkriːʃən/

accretion

蓄積
Meaning
The process of growth or increase, typically by the gradual accumulation of additional layers or matter.
Example
The accretion of wealth allowed him to invest in various projects.
財産の蓄積により、彼はさまざまなプロジェクトへの投資を可能にした。
C2 adjective /ɔːˈrɪfərəs/

auriferous

金鉱を含む
Meaning
Containing or producing gold.
Example
The miners discovered an auriferous vein in the mountains.
鉱山労働者は山で金鉱を含む鉱脈を発見しました。
C2 adjective /ˈæpəˌleɪt/

appellate

控訴に関連する
Meaning
relating to appeals in a court of law
Example
The case was taken to an appellate court.
その事件は控訴裁判所に持ち込まれました。
C2 noun/adjective /ælˈbaɪ.noʊ/

albino

アルビノ (色素が欠けている人/動物)
Meaning
A person, animal, or plant lacking normal pigmentation, resulting in pale skin, hair, and eyes.
Example
The albino rabbit had white fur and pink eyes.
アルビノウサギは白い毛とピンクの目を持っていました。
C2 noun /ˌæk.wiˈes.əns/

acquiescence

黙示的同意
Meaning
The reluctant acceptance of something without protest.
Example
His silent acquiescence to unfair rules was surprising.
不公平なルールへの彼の黙示的な同意は驚くべきものでした。
C2 verb /ˈɔːɡər/

augur

予兆する
Meaning
To be a sign of something to come; to predict or foretell.
Example
Dark clouds augur a coming storm.
暗い雲が来る嵐を予示しています。
C2 noun /ˌeɪd də ˈkæmp/

aide-de-camp

上級将校の秘密の補佐役として働く軍人
Meaning
A military officer acting as a confidential assistant to a senior officer.
Example
The general was accompanied by his aide-de-camp during the ceremony.
儀式の間、将軍は自分のエイド・デ・キャンプと共に出席しました。
C2 adjective /əˈpɜːrtənənt/

appurtenant

附属
Meaning
Belonging to or associated with something, often used in legal/property contexts.
Example
The right of way is appurtenant to the landowner’s property.
通行権は土地所有者の財産に付随しています。
C2 adjective /əˈkjuː.zəˌtɔːr.i/

accusatory

非難の
Meaning
Suggesting blame or indicating someone has done wrong.
Example
He gave her an accusatory glance.
彼は彼女に非難の目を向けた。
C2 adjective /əˈθɜːrst/

athirst

渇望している, 熱望している
Meaning
Very eager or desirous for something.
Example
The explorer was athirst for adventure.
探検家は冒険に渇望していた。
C2 noun /ˈæl.kə.laɪ ækt/

Alkali Act

アルカリ法案
Meaning
A British law passed in 1863 to regulate the emission of hydrochloric acid gas from alkali works, representing one of the first pieces of environmental legislation.
Example
The Alkali Act of 1863 was one of the first environmental laws.
1863年のアルカリ法案は最初の環境法の一つでした。
C2 noun /ˈæl.mɪ.rə/

Almirah

クローゼット
Meaning
a large cupboard or wardrobe used for storing clothes and other items
Example
I keep all my clothes in the wooden almirah.
私はすべての衣服を木製のアルミラーに保管します。
C2 noun /əˈluː.vi.əm/

alluvium

沖積土
Meaning
Fertile soil deposited by flowing water, especially in riverbanks.
Example
The alluvium in riverbanks is highly fertile for agriculture.
川の岸辺にあるアリューヴィウムは農業に非常に肥沃です。
C2 verb /ˈædjʊˌleɪt/

adulate

過剰に賛美する
Meaning
to praise or flatter excessively
Example
The fans adulated the actor after his performance.
ファンたちは彼のパフォーマンスの後、俳優を賛美しました。
C2 verb /əˈkuːtə/

accoutre

装備する
Meaning
to dress or equip, especially in something impressive or elaborate
Example
The knight was accoutred in shining armor.
騎士は輝く鎧で装備されていました。
C2 noun /əˈdɛpt.nəs/

adeptness

熟練と巧妙さ
Meaning
Skill and dexterity in a task.
Example
His adeptness in negotiations helped close the deal successfully.
交渉における彼の熟練さは、契約を成功裡に締結するのに役立った。
C2 noun əˌklaɪ.mə.tɪˈzeɪ.ʃən

acclimatization

適応
Meaning
The process of adapting to a new environment or condition.
Example
The hikers needed time for acclimatization to high altitudes.
登山者は高い標高に適応するために時間が必要でした。
C2 adverb /əˈmʌk/

amok

制御不能
Meaning
Behaving uncontrollably and disruptively.
Example
The angry mob ran amok after the verdict was announced.
怒った群衆は判決が発表された後、制御不能で走り回った。
C2 adjective /ˈækwɪˌlaɪn/

aquiline

ワシのくちばしのような
Meaning
curved like an eagle's beak; hooked
Example
He had an aquiline nose that gave him a distinguished appearance.
彼はワシのくちばしのような鼻を持っており、それが彼に優れた外見を与えていました。
C2 adjective /eɪˈrɪðmɪk/

arrhythmic

不整脈
Meaning
Lacking a regular rhythm or beat.
Example
The patient had an arrhythmic heartbeat.
患者は不整脈を持っていた。
C2 verb /ˈæktʃueɪt/

actuate

作動させる
Meaning
to put into action or motion; to motivate or activate
Example
The engineer actuated the machine with a simple switch.
エンジニアは簡単なスイッチで機械を作動させました。
C2 noun /ˈeɪʒən swɒmp iːl/

Asian swamp eel

アジアドジョウウナギ
Meaning
a snake-like freshwater fish that can survive in muddy waters and is considered a delicacy in South Asian cuisine
Example
Asian swamp eel can breathe air and survive in shallow muddy waters.
アジアドジョウウナギは空気を吸い、浅い泥の水で生き残ることができます。
C2 adjective /ˈæfərənt/

afferent

求心
Meaning
carrying impulses toward a central organ or part, especially toward the brain or spinal cord
Example
Afferent nerves carry signals from the body to the brain.
求心神経は体から脳に信号を運びます。
C2 noun /əˈbaɪdəns/

abidance

遵守
Meaning
the act of following, accepting, or complying with something
Example
Her abidance by the rules impressed the committee.
規則を守ることが委員会に印象を与えました。
C2 adjective /əˈsɜːrbɪk/

acerbic

辛辣
Meaning
sharp, harsh, or bitter in tone or taste
Example
His acerbic comments offended many people in the meeting.
彼の辛辣なコメントは会議で多くの人々を侮辱しました。
C2 noun /ˌɛərəˈstætɪks/

aerostatics

エアロスタティクス
Meaning
The branch of physics that deals with the equilibrium of air and gases and the forces acting on bodies in them.
Example
Aerostatics is essential for understanding how balloons float.
エアロスタティクスは、気球がどのように浮かぶかを理解するために不可欠です。
C2 noun /ˌɔːskʌlˈteɪʃən/

auscultation

聴診
Meaning
The act of listening to internal sounds of the body, typically using a stethoscope.
Example
The doctor performed auscultation to check the patient’s lungs.
医者は患者の肺を調べるために聴診を行いました。
C2 noun /ˌænθrəpəˈsɛntrɪzəm/

anthropocentrism

人間中心主義
Meaning
The belief that human beings are the most important or central element of existence.
Example
Anthropocentrism often shapes environmental policies.
人間中心主義はしばしば環境政策を形作る。
C2 verb /ˌæntɪˈsiːd/

antecede

前に来る
Meaning
to come before in time or order
Example
A short introduction usually antecedes the main text.
短い紹介は通常、本文の前に来ます。
C2 noun /ˈɑːm.lət/

Armlet

アームレット
Meaning
a band worn around the upper arm as an ornament
Example
The traditional dancer wore golden armlets that gleamed in the spotlight.
伝統的なダンサーは、スポットライトの中で輝く金色のアームレットを着けていました。
C2 verb /əˈbɛt/

abet

Meaning
to encourage or assist someone to commit a crime or wrongdoing
Example
He was accused of abetting the criminals in their escape.
C2 noun /ˈæpəˌθɛm/

apothegm

格言, 名言
Meaning
A short, witty, and instructive saying or maxim.
Example
His speech was filled with apothegms about life and success.
彼のスピーチは人生と成功に関する格言でいっぱいでした。
C2 noun /ˈiːdʒɪs/

aegis

保護
Meaning
The protection, backing, or support of a particular person or organization.
Example
The project was carried out under the aegis of the United Nations.
このプロジェクトは国連の庇護の下で実施されました。
C2 noun /ˈæpəplɛksi/

apoplexy

脳卒中や極端な怒りによる突然の意識喪失や制御の喪失
Meaning
A sudden loss of consciousness or control due to stroke or extreme anger.
Example
The old man nearly had apoplexy when he heard the shocking news.
その老人は衝撃的なニュースを聞いてほとんどアポプレキシーを起こしました。
C2 adjective əˈsɪd.ju.əs

assiduous

勤勉な、熱心な
Meaning
Showing great care and perseverance; diligent and hardworking.
Example
His assiduous efforts led to a successful career.
彼の勤勉な努力は成功したキャリアにつながった。
C2 noun /ˌæv.oʊˈkeɪ.ʃən/

avocation

副業
Meaning
a hobby or minor occupation pursued in addition to one's main work
Example
Painting is his avocation after office hours.
絵画はオフィスの後の彼の副業です。
C2 verb /əˈbeɪs/

abase

卑下する
Meaning
to belittle or degrade someone
Example
He refused to abase himself before the king.
彼は王の前で自分を卑下するのを拒否した。
C2 adjective /ˌæn.θrə.pəˈdʒen.ɪk/

anthropogenic

人為的
Meaning
Originating in human activity; caused by humans.
Example
Climate change is largely due to anthropogenic activities.
気候変動は主に人為的な活動によるものです。
C2 noun /əˈmʊr/

amour

秘密の愛
Meaning
A secret or illicit love affair.
Example
The novel tells the story of a forbidden amour between two characters.
その小説は、二人の登場人物の間の禁じられたアムールの物語を語っています。
C2 verb /əkˈsiːd/

accede

同意する
Meaning
to agree to a request, proposal, or demand; to assume an office or position
Example
The government finally acceded to the demands of the protesters.
政府はついに抗議者の要求に応じた。
C2 noun /ˈænɪ siːd/

Ani seed

アニス
Meaning
Small aromatic seeds used as a spice and for medicinal purposes, with a sweet licorice-like flavor
Example
Anise seeds are often used in traditional desserts and teas.
アニスの種は伝統的なデザートやお茶にしばしば使われます。
C2 noun /əˈnæθəmə/

anathema

アナセマ / 嫌悪された物
Meaning
something or someone intensely disliked or strongly condemned
Example
Violence is anathema to her peaceful nature.
暴力は彼女の平和的な性格にはアナセマです。
C2 verb /əˈbreɪd/

abrade

摩擦で擦り減らす
Meaning
to scrape or wear away the surface by friction or erosion
Example
The rough cloth can easily abrade the skin.
ザ・ラフクロスは皮膚を簡単に擦ります。
C2 noun ˈɔː.tɑː.ki

autarky

自給自足, 経済的独立
Meaning
Economic independence or self-sufficiency; a policy of establishing a self-sufficient national economy.
Example
Some nations aim for autarky to reduce reliance on imports.
いくつかの国は輸入への依存を減らすためにオータキーを目指しています。
C2 noun /ˈæl.ɪ.mənt/

aliment

食物
Meaning
food or nourishment that sustains life
Example
Fruits and vegetables are important aliments for a healthy body.
果物と野菜は健康な体のための重要な食物です。
C2 noun /əˌbɑː.məˈneɪ.ʃən/

abomination

忌まわしい物
Meaning
a thing that causes disgust or hatred
Example
Slavery was considered an abomination.
奴隷制度は忌まわしい物と見なされていました。
C2 verb /ˈæbrəɡeɪt/

abrogate

廃止する
Meaning
To formally repeal, cancel, or abolish a law, agreement, or custom.
Example
The government decided to abrogate the outdated treaty.
政府は古い条約を廃止することを決定しました。
C2 noun /əˈpɒθəˌkɛri/

apothecary

薬剤師
Meaning
A historical term for a person who prepared and sold medicines and drugs.
Example
The village apothecary provided remedies for many common illnesses.
村のアポセカリーは多くの一般的な病気に対する治療法を提供しました。
C2 verb /əˈdjuːs/

adduce

証拠や理由を提供する
Meaning
To provide evidence or reasons to support an argument or idea.
Example
The lawyer adduced several examples to support his case.
弁護士は自分のケースを支持するためにいくつかの例を挙げた。
C2 noun /ˈæn.ə.lɪst/

annalist

年表作成者
Meaning
A person who writes annals or records events year by year.
Example
The annalist carefully documented the events of the king's reign.
アナリストは王の統治期間の出来事を慎重に記録しました。
C2 adjective /əˈluːviəl/

alluvial

沖積の
Meaning
Relating to or derived from alluvium (loose soil or sediment deposited by rivers).
Example
The farmers cultivate crops on the fertile alluvial plains.
農民たちは肥沃な沖積平原で作物を栽培します。
C2 noun /əˈvɪdəti/

avidity

熱意
Meaning
extreme eagerness or enthusiasm
Example
He accepted the offer with avidity.
彼は熱意を持ってその提案を受け入れました。
C2 noun /əˌpɒθiˈoʊsɪs/

apotheosis

頂点, 完璧な例
Meaning
The highest point of development; the perfect example of something; the elevation of someone to divine status.
Example
Many see the Renaissance as the apotheosis of art and culture in Europe.
多くの人々はルネサンスをヨーロッパの芸術と文化の頂点と見なしています。
C2 noun /əˈsper.ɪ.ti/

asperity

Meaning
Harshness of tone, manner, or surface.
Example
She spoke with asperity when she was interrupted.
C2 noun /ˈæmpərˌsænd/

ampersand

アンパーサンド
Meaning
The symbol '&' used to represent the word 'and'.
Example
Use an ampersand instead of writing the word 'and' in the company name.
会社名に'and'の代わりにアンパーサンドを使用してください。
C2 adjective /ˌævəˈrɪʃəs/

avaricious

貪欲な
Meaning
having or showing extreme greed for wealth or material gain
Example
The avaricious landlord increased the rent unfairly.
貪欲な家主は不公平に家賃を上げました。
C2 noun /ˌænəlˈdʒiːziə/

analgesia

鎮痛
Meaning
The inability to feel pain while still conscious.
Example
The doctor induced analgesia before performing the procedure.
医者は手術を行う前に鎮痛を誘発した。
C2 noun /ˈɑːrkeɪndʒəl/

archangel

Meaning
A high-ranking angel, often considered a chief messenger or leader among angels.
Example
Michael is often depicted as the most powerful archangel.
C2 noun əˌdʌl.təˈreɪ.ʃən

adulteration

不正
Meaning
The action of making something poorer in quality by the addition of another substance.
Example
Adulteration of food is a serious health risk.
食品の不正は健康に対する深刻なリスクです。
C2 verb /ˈæmərˌtaɪz/

amortize

償却
Meaning
To gradually reduce or pay off a debt with regular payments.
Example
They plan to amortize the mortgage over 20 years.
彼らは20年間で住宅ローンをアモーティゼする予定です。
C2 noun /əˈplɒm/

aplomb

Meaning
Complete and confident self-assurance or poise.
Example
She handled the difficult questions with aplomb.
C2 verb /ˌækwiˈɛs/

acquiesce

黙って従う
Meaning
to accept something reluctantly but without protest
Example
She decided to acquiesce to her parents’ wishes.
彼女は両親の願いを黙って従うことに決めました。
C2 noun /ˈɔːrɪkl̩/

auricle

耳の外側部分
Meaning
The external part of the ear; also an upper chamber of the heart in anatomy.
Example
The doctor examined the patient’s auricle for signs of infection.
医師は患者の耳の外側部分に感染の兆候がないか調べました。
C2 adjective /ədˈmɒnɪtəri/

admonitory

警告の
Meaning
giving or conveying a warning or reprimand
Example
She gave him an admonitory glance.
彼女は彼に警告のまなざしを向けました。
C2 noun əˈlæk.rə.t̬i

alacrity

迅速で楽しい準備
Meaning
Brisk and cheerful readiness.
Example
He accepted the challenge with alacrity.
彼はアラクリティで挑戦を受け入れた。
C2 noun /ˈænsɛstrɪs/

ancestress

女性の祖先
Meaning
a female ancestor; a woman from whom one is descended
Example
She discovered that her ancestress came from a small village in Bengal.
彼女は自分の女性の祖先がベンガルの小さな村出身だと知った。
C2 adjective /ˈæstrəl/

astral

Meaning
Relating to the stars or to spiritual, non-physical realms.
Example
Some believe in astral projection, the ability to leave the body and travel spiritually.
C2 noun /ˈæk.rɪ.moʊ.ni/

acrimony

Meaning
Bitterness and anger, especially in speech or behavior.
Example
The divorce was filled with acrimony and disputes.
C2 verb /əˈvaʊtʃ/

avouch

主張する
Meaning
to affirm or assert something as true
Example
He avouched his innocence before the judge.
彼は裁判官の前で無実を主張しました。
C2 adjective /əˈstrɪndʒənt/

astringent

厳しい
Meaning
sharp or severe in manner or style; also describes a substance that contracts skin or body tissues
Example
Her astringent tone silenced the noisy class.
彼女の厳しい口調は、騒々しいクラスを静めた。
C2 adjective /əˈkwɪzətɪv/

acquisitive

Meaning
excessively interested in acquiring money or material things
Example
The acquisitive businessman bought every piece of land he could find.
C2 noun /ˌæpəˈzɪʃən/

apposition

同格 (並列文法)
Meaning
a grammatical construction in which two elements are placed side by side, with one explaining the other
Example
In the phrase 'my friend John,' the word 'John' is in apposition to 'my friend.'
'私の友人ジョン'というフレーズでは、'ジョン'という単語が'私の友人'とアポジションにあります。
C2 adjective /ɔːˈrɔːrəl/

auroral

オーロラに関連する
Meaning
Relating to or resembling the aurora, especially the northern lights.
Example
The scientists observed auroral activity in the night sky.
科学者たちは夜空でオーロラルの活動を観察しました。
C2 noun /ˈækmi/

acme

頂点
Meaning
the highest point of achievement or excellence
Example
Winning the award was the acme of his career.
賞を獲得することが彼のキャリアの頂点でした。
C2 noun /ˈeɪ.viˌɛr.i/

aviary

鳥小屋
Meaning
a large enclosure for keeping birds
Example
The zoo built a new aviary for exotic parrots.
動物園はエキゾチックなオウムのために新しい鳥小屋を作った。
C2 noun /əˈkwaɪərmənt/

acquirement

取得; 習得
Meaning
the act of acquiring something; something that has been acquired, especially a skill or possession
Example
Language proficiency is an important acquirement for global careers.
語学力はグローバルなキャリアにとって重要な取得です。
C2 verb /ˌæd ˈlɪb/

ad-lib

即興
Meaning
to speak or perform without preparation; to improvise
Example
The comedian ad-libbed a joke when the microphone failed.
コメディアンはマイクの故障でジョークをアドリブしました。
C2 adjective, adverb /əˈfʊt/

afoot

進行中
Meaning
In progress; happening or being prepared.
Example
There are several new projects afoot in the company.
会社にはいくつかの新しいプロジェクトが進行中です。
C2 noun ˌæɡ.roʊˈiː.koʊˌsɪs.təm

agroecosystem

農業生態系
Meaning
An ecological system centered on agricultural activities and processes.
Example
A healthy agroecosystem improves soil fertility.
健康な農業生態系は土壌の肥沃度を改善します。
C2 noun /əˈmɛrɪkəˌnɪzəm/

americanism

Meaning
A word, phrase, or practice characteristic of American English or culture.
Example
The term 'sidewalk' is an Americanism, while 'pavement' is used in British English.
C2 noun /ˌæɡ.rəˈdeɪ.ʃən/

aggradation

堆積物によって土地が作られるプロセス
Meaning
The process of land being built up by sediment deposition.
Example
Aggradation helps in the natural expansion of riverbanks.
アグレデーションは河川の自然な拡張を助けます。
C2 noun əˈkjuː.ə.ti

acuity

鋭敏さ
Meaning
Sharpness or keenness of thought, vision, or hearing.
Example
His intellectual acuity made him a brilliant scientist.
彼の知的な鋭敏さは彼を優れた科学者にしました。
C2 noun /ˈænɪməlˌkjuːl/

animalcule

動物微生物
Meaning
A microscopic animal, especially a protozoan or other minute organism.
Example
The scientist observed an animalcule moving under the microscope.
科学者は顕微鏡の下で動物微生物が動いているのを観察しました。
C2 adjective /əˈpɒ.krɪ.fəl/

apocryphal

疑わしい
Meaning
Of doubtful authenticity, though widely circulated as true.
Example
The story about him saving the village is probably apocryphal.
彼が村を救ったという話は、おそらく疑わしい。
C2 adjective /æbˈhɔːr.ənt/

Abhorrent

忌まわしい; 嫌悪すべき
Meaning
extremely unpleasant and causing disgust; detestable
Example
The idea of animal cruelty is abhorrent to most people.
動物虐待の考えはほとんどの人々にとって嫌悪感を抱かせます。
C2 noun /əˈdɛndəm/

addendum

補遺
Meaning
an additional item or piece of information added at the end of a document or book
Example
The report included an addendum with updated statistics.
報告書には更新された統計データが含まれている補遺が含まれていた。
C2 adjective /əˈsɛt.ɪk/

ascetic

禁欲的
Meaning
Practicing strict self-denial and abstaining from worldly pleasures, often for religious reasons.
Example
He lived an ascetic life in the mountains, far from worldly comforts.
彼は山の中で禁欲的な生活を送り、世俗的な快適さから遠ざかっていた。
C2 adjective /ɑːrˈbɔːr.i.əl/

arboreal

樹木に関する
Meaning
Relating to trees or living in trees; tree-dwelling.
Example
Monkeys are arboreal animals that spend most of their time in trees.
サルは樹上性の動物で、ほとんどの時間を木の上で過ごします。
C2 noun /ˌɔːltərˈkeɪʃən/

altercation

口論, 言い争い
Meaning
a noisy argument or quarrel
Example
There was a brief altercation between the two drivers.
二人のドライバーの間で短い口論がありました。
C2 verb /ˈæbnɪˌɡeɪt/

abnegate

放棄する
Meaning
to deny or renounce something, especially a right or desire
Example
She chose to abnegate her personal interests for the sake of the team.
彼女はチームのために自分の個人的な利益を放棄することを選びました。
C2 adjective /əˈbɑː.mə.nə.bəl/

abominable

忌まわしい
Meaning
causing moral revulsion; extremely unpleasant
Example
The prisoners were kept in abominable conditions.
囚人たちは忌まわしい状況で拘束されていた。