C1 adjective /juːˈbɪkwɪtəs/

ubiquitous

普遍的

Meaning

Existing or being everywhere at the same time.

Example

Social media has become ubiquitous among young people.

ソーシャルメディアは若者の間で普及しています。

C1 adverb /ʌnˈnætʃrəli/

unnaturally

不自然に

Meaning

in a way that is not natural or normal; excessively or strangely

Example

He smiled unnaturally, making everyone feel uncomfortable.

彼は不自然に笑い、皆を居心地悪くさせた。

C1 adjective /ʌnˈbraɪdld/

unbridled

抑制のない

Meaning

Uncontrolled and unrestrained.

Example

The protesters showed unbridled enthusiasm for change.

抗議者は変革に対して抑えきれない熱意を示しました。

C2 adjective /ˌʌnɪkˈsɛpʃənəbl/

unexceptionable

非の打ち所がない

Meaning

Not open to objection; acceptable and unobjectionable

Example

His behavior was unexceptionable throughout the event.

彼の行動はイベント中ずっと非の打ち所がなかった。

C1 adjective /ʌlˈtɪəriər/

ulterior

隠された動機

Meaning

hidden or secret, often with a selfish motive

Example

He invited her with an ulterior motive.

彼は隠された動機で彼女を招待した。

C2 noun /ˈʌŋɡwənt/

unguent

軟膏

Meaning

A soothing or healing ointment applied to the skin.

Example

The doctor applied an unguent to heal the burn.

医者は火傷を治すために軟膏を塗った。

B2 adjective /ˌʌnəˈveɪləbəl/

unavailable

利用できない

Meaning

Not able to be obtained, reached, or used; not present or accessible.

Example

The manager was unavailable to take calls during the meeting.

マネージャーは会議中に電話に出られませんでした。

C1 adjective /ˌʌnsəˈfɪstɪˌkeɪtɪd/

unsophisticated

未洗練

Meaning

Lacking worldly experience, refinement, or complexity.

Example

The villagers led an unsophisticated but happy life.

村人たちは未洗練だが、幸せな生活を送っていた。

C1 adjective /ʌnˈsiːmli/

unseemly

不適切な

Meaning

Not proper or appropriate in behavior or appearance; unbecoming.

Example

His unseemly remarks embarrassed everyone at the dinner table.

彼の不適切な発言はディナーテーブルで皆を困らせました。

B1 adjective /ˌʌnbɪˈliːvəbəl/

Unbelievable

信じられない

Meaning

impossible to believe; extremely surprising or remarkable

Example

The magician's performance was absolutely unbelievable.

魔法使いのパフォーマンスは絶対に信じられなかった。

B2 noun /ʌnˈrest/

Unrest

不安; 動乱; 社会的または政治的混乱

Meaning

a state of dissatisfaction and disturbance; social or political disorder

Example

The economic crisis led to widespread social unrest.

経済危機は広範な社会的不安を引き起こしました。

C1 adjective /ˌʌnəkˈnɒlɪdʒd/

unacknowledged

認められない

Meaning

Not recognized, admitted, or accepted; ignored or unnoticed

Example

Her contributions to the project went unacknowledged.

彼女のプロジェクトへの貢献は認められなかった。

C1 noun /ʌnkənˈsɜːrn/

Unconcern

無関心

Meaning

lack of worry or interest; indifference

Example

She showed complete unconcern about the criticism.

彼女は批評に対して完全に無関心を示しました。

C1 verb /ˈʌndərkʌt/

undercut

Meaning

to sell at a lower price than a competitor; to weaken or undermine something

Example

The company tried to undercut its rivals by offering lower prices.

B2 adjective /ˌʌnkənˈvɛnʃənl/

unconventional

型破りの

Meaning

not based on or conforming to what is generally done or believed

Example

Her unconventional approach to teaching inspired her students to think creatively.

彼女の型破りの教育アプローチは、生徒たちに創造的に考えるよう促しました。

C1 noun /ˈʌp.rɔːr/

Uproar

騒動; 騒ぎ; 騒音

Meaning

a loud and emotional noise or disturbance; public outcry

Example

The announcement caused an uproar among the students.

その発表は学生たちの間で騒動を引き起こしました。

C2 verb /ˈʌndərˌmæn/

underman

人手不足

Meaning

to supply with fewer workers or personnel than needed

Example

The hospital was undermanned during the flu outbreak.

インフルエンザの流行時に病院は人手不足でした。

B1 adjective /ʌnˈwɒn.tɪd/

Unwanted

望まれない

Meaning

not desired or welcome; not wanted

Example

He felt like an unwanted guest at the meeting.

彼は会議で望まれない客のように感じた。

A1 noun /ˌjuːnɪˈvɜːrsɪti/

university

大学

Meaning

an institution of higher education and research, which grants academic degrees

Example

She is studying law at the university.

彼女は大学で法学を学んでいます。

C1 adjective /ʌnˈtoʊld/

Untold

無数の; 無限の

Meaning

very great in amount or degree; countless; immeasurable

Example

The earthquake caused untold damage to the city.

地震は都市に無数の損害を与えました。

B1 adjective /ʌnˈkaɪnd/

Unkind

無愛想; 不親切

Meaning

cruel; not nice or caring toward others

Example

It was unkind of him to make fun of her appearance.

彼が彼女の外見をからかうのは不親切だった。

B2 adjective /ʌnˈtʃeɪndʒəbəl/

Unchangeable

変更不可能な; 固定された;

Meaning

not able to be changed or altered; fixed and permanent

Example

The laws of physics are unchangeable principles that govern the universe.

物理法則は変更不可能な原則であり、宇宙を支配しています。

B2 verb /ʌnˈkʌvə(r)/

uncover

明らかにする

Meaning

to reveal something that was hidden or secret

Example

The investigation uncovered new evidence.

調査で新しい証拠が明らかになった。

B2 adjective /ʌnˈlɔːfl/

Unlawful

違法; 不法

Meaning

not authorized by law; illegal

Example

The court declared the search unlawful.

裁判所はその捜索を不法と宣言しました。

C1 verb /ˌʌndəˈreɪt/

underrate

過小評価

Meaning

to fail to recognize the full value or importance of something or someone

Example

Many people underrate the benefits of regular exercise.

多くの人々が定期的な運動の利点を過小評価しています。

B2 adjective /ʌnˈfeɪ.vər.ə.bəl/

Unfavourable

不利な; 逆境の

Meaning

not helpful or advantageous; adverse

Example

The weather conditions were unfavourable for our outdoor event.

悪天候は私たちの屋外イベントには不利でした。

C2 verb /ʌnˈfɛtər/

unfetter

制約から解放する

Meaning

to release from restraint or restriction; to free

Example

The new law will unfetter small businesses from excessive regulations.

新しい法律は小規模なビジネスを過剰な規制から解放します。

C1 verb /ˌʌndərˈsteɪt/

understate

過小評価する

Meaning

To describe something as being less important or serious than it really is.

Example

He tends to understate his achievements.

彼は自分の業績を過小評価する傾向があります。

B1 adjective /ʌnˈmærid/

unmarried

未婚

Meaning

Not married; single.

Example

He is thirty-five and still unmarried.

彼は三十五歳で、まだ未婚です。

C1 verb /ʌnˈsɛtl/

unsettle

動揺させる

Meaning

To disturb or make someone feel anxious or uneasy.

Example

The sudden news unsettled the entire community.

突然のニュースはコミュニティ全体を動揺させた。

B2 noun ˌjuːtɪlaɪˈzeɪʃən

utilization

利用

Meaning

The action of making practical and effective use of something.

Example

Increased plastic utilization calls for better waste management.

プラスチックの利用増加は、より良い廃棄物管理を求めています。

B1 adjective /ʌnˈnesəseri/

Unnecessary

不必要な; 無駄な

Meaning

not needed; not required; pointless

Example

The meeting was unnecessary since all decisions were already made.

その会議は必要ありませんでした、すべての決定はすでに下されていました。

B2 adjective /ʌnˈwaɪz/

unwise

賢明でない

Meaning

Showing poor judgment; not sensible or prudent.

Example

It would be unwise to invest all your money in one company.

すべてのお金を1つの会社に投資するのは賢明でないことです。

C1 adjective /ʌnˈsoʊld/

unsold

未販売の

Meaning

not sold; remaining without a buyer

Example

The unsold goods were returned to the warehouse.

未販売の商品は倉庫に戻されました。

B2 adjective /ʌnˈdʒʌst/

Unjust

不当な; 不正な

Meaning

not fair or right; morally wrong

Example

The punishment was unjust for such a minor offense.

その罰は軽微な違反に対して不当でした。

B1 adjective /ʌnˈjuː.ʒu.əl/

Unusual

異常な; 奇妙な;

Meaning

not typical; strange; different from what is normal

Example

She wore an unusual dress to the party.

彼女はパーティーに異常なドレスを着ていた。

C1 noun /ˈʌp.raɪt.nəs/

Uprightness

誠実; 正直

Meaning

the quality of being honest and morally correct; integrity

Example

His uprightness in business dealings earned him great respect.

彼のビジネスでの正直さは、彼に大きな尊敬をもたらした。

A2 verb /ʌpˈset/

upset

困らせる

Meaning

to make someone worried, sad, or angry; to disturb

Example

The bad news upset everyone.

悪いニュースはみんなを upset した。

C1 adjective ʌnˈpær.ə.leld

Unparalleled

比類のない

Meaning

Having no equal; unmatched, peerless, and supreme in quality or achievement.

Example

The unparalleled beauty of the Taj Mahal amazes visitors.

タージ・マハルの比類のない美しさが訪問者を驚かせます。

B2 adjective /ʌnˈfeɪθ.fəl/

Unfaithful

不忠実

Meaning

not loyal or true to a spouse, partner, or commitment

Example

He was unfaithful to his wife for many years.

彼は何年も妻に不忠実でした。

B1 verb /juˈnaɪt/

unite

団結する

Meaning

to join together or combine; to bring people or things together

Example

The crisis helped unite the community.

危機はコミュニティを団結させる手助けをした。

B2 adjective /ʌnˈprɒf.ɪ.tə.bl̩/

Unprofitable

採算が取れない

Meaning

not yielding profit or gain; not producing financial benefit

Example

The unprofitable business was forced to close down after three years.

採算が取れないビジネスは3年後に閉店を余儀なくされました。

C1 adjective /ˈʌndərhænd/

underhand

不正

Meaning

done secretly and dishonestly; deceitful

Example

The politician was accused of using underhand tactics to win the election.

その政治家は選挙に勝つために不正な手段を使ったとして非難されました。

B1 adjective /ʌnˈlaɪkli/

Unlikely

ありそうにない; 予想外の

Meaning

not likely to happen; improbable

Example

It's unlikely to rain today with such clear skies.

こんなに晴れた空では、今日は雨が降る可能性は低い。

A2 noun /ʌmˈbrɛlə/

umbrella

傘

Meaning

A device used for protection against rain or sun, typically consisting of a collapsible canopy mounted on a central rod.

Example

She opened her umbrella as it started to rain.

雨が降り始めたので、彼女は傘を開いた。

C1 adjective ˌʌn.pəˈtɜːbd

unperturbed

何かに悩まされたり、動揺したりしない; 冷静で落ち着いている

Meaning

Not worried or disturbed by something; calm and composed.

Example

She remained unperturbed despite the challenges.

彼女は挑戦にもかかわらず冷静さを保っていた。

A2 adjective /ˈjuːʒəl/

usual

通常

Meaning

habitually or typically occurring or done

Example

It’s our usual meeting spot.

これは私たちの通常の会議場所です。

C2 noun /ˈjuːnɪvəˌlɛns/

univalence

単価性

Meaning

The state of having a single valence or combining power, especially in chemistry.

Example

Hydrogen is characterized by its univalence in chemical reactions.

水素は化学反応においてその単価性によって特徴づけられています。

C2 adjective /ʌnˈwəʊntɪd/

unwonted

異常

Meaning

Unusual, uncommon, or out of the ordinary.

Example

She spoke with an unwonted gentleness that surprised everyone.

彼女は予想外の優しさで話し、皆を驚かせました。

A1 pronoun /ʌs/

us

私たち

Meaning

used to refer to the speaker and one or more other people as the object of a verb or preposition

Example

She gave us a gift.

彼女は私たちに贈り物をくれました。

C1 adjective ʌnˈjiːl.dɪŋ

unyielding

揺るぎないまたは堅い

Meaning

Not easily broken or giving in to pressure.

Example

Her unyielding determination helped her overcome all challenges.

彼女の揺るぎない決意が彼女をすべての挑戦を乗り越えさせました。

B2 adjective /ʌnəˈfreɪd/

unafraid

恐れない

Meaning

Not feeling fear; brave or courageous

Example

She walked into the dark room, unafraid of what might be inside.

彼女は暗い部屋に入り、恐れないで何があるかを見た。

B2 noun /ˌʌnəˌveɪləˈbɪləti/

unavailability

利用不可

Meaning

The state of being not available or not accessible.

Example

The unavailability of the manager caused a delay in the project.

マネージャーの不在がプロジェクトの遅延を引き起こした。

B1 preposition, adverb, adjective /ˌʌndərˈniːθ/

underneath

下に、下側に

Meaning

Located directly below or beneath something

Example

The keys were hidden underneath the pile of papers.

鍵は紙の山の下に隠されていました。

C2 noun /ɜːrˈbænɪti/

urbanity

都会的な気品

Meaning

refined courtesy, elegance, and sophistication in manner

Example

Her urbanity made her popular among diplomats and leaders.

彼女の都会的な気品は、外交官やリーダーの間で人気を集めました。

B2 adjective /ˌʌnrɪˈzɒlvd/

unresolved

未解決の

Meaning

not solved or settled; remaining undecided or unclear

Example

The dispute remains unresolved despite several meetings.

その問題は何度も会議をしたにもかかわらず未解決のままだ。

B2 noun /ʌnˈkaɪndnəs/

unkindness

不親切

Meaning

lack of kindness; cruel or inconsiderate behavior

Example

His unkindness hurt her feelings deeply.

彼の不親切は彼女の気持ちを深く傷つけた。

C2 adjective /ʌnˈflæpəbəl/

unflappable

冷静沈着

Meaning

calm and composed, especially in difficult situations

Example

Despite the crisis, he remained unflappable and confident.

危機にもかかわらず、彼は冷静沈着で自信に満ちていた。

B2 verb /ˌʌndərˈteɪk/

undertake

引き受ける

Meaning

to commit to and begin a task or project; to take on responsibility

Example

She decided to undertake a challenging project.

彼女は挑戦的なプロジェクトを始めることに決めました。

C2 verb /ˈʌndərˌraɪt/

underwrite

Meaning

To guarantee financial support, especially by agreeing to cover losses or risks; in insurance, to assess and accept risks.

Example

The bank agreed to underwrite the company's new bond issue.

B1 adverb /ʌnˈjuːʒuəli/

unusually

異常に

Meaning

in a way that is not typical or expected; to an uncommon degree

Example

It was unusually cold for this time of year.

この時期にしては異常に寒かった。

B2 adjective /ˌʌndɪˈveləpt/

Undeveloped

未開発; 未成熟; 原始的

Meaning

not yet developed; immature or primitive

Example

The undeveloped land was later turned into a park.

未開発の土地は後に公園に変わりました。

C1 adjective /ʌnˈtʃælɪndʒd/

Unchallenged

挑戦されていない; 反対なしに受け入れられた; ライバルなし

Meaning

not disputed or questioned; accepted without opposition; having no rival

Example

He remained the unchallenged champion for five years.

彼は5年間、挑戦されていないチャンピオンであり続けました。

A2 adjective /ʌnˈlʌki/

Unlucky

不運; ラッキーでない

Meaning

having bad luck; unfortunate

Example

He was unlucky to miss the winning shot.

彼は勝つシュートを外して不運だった。

B2 adjective /ˈʌl.tɪ.mət/

Ultimate

究極; 最後; 最高の

Meaning

being the best or most extreme example of its kind; final; last

Example

This is the ultimate test of your skills.

これがあなたのスキルの究極のテストです。

C1 adverb /ˌʌnkənˈvɛnʃənəli/

unconventionally

型破りに

Meaning

in a way that is not based on or conforming to accepted standards or norms

Example

She dresses unconventionally, mixing bold colors and patterns that surprise everyone.

彼女は型破りに服装をしており、大胆な色と柄を組み合わせて皆を驚かせる。

B2 noun /ˈjuː.sɪdʒ/

Usage

使用

Meaning

the action of using something; the way in which words are used in a language

Example

The dictionary explains the correct usage of difficult words.

辞書は難しい言葉の正しい使い方を説明しています。

C1 noun /ˈʌndərˌɡɑːrmənt/

undergarment

下着

Meaning

a piece of clothing worn under outer clothes, usually next to the skin

Example

He bought new undergarments for the wedding.

彼は結婚式のために新しい下着を買いました。

C2 adjective /ˌʌltrəˈmʌndeɪn/

ultramundane

超越的

Meaning

Relating to things beyond the physical world; supernatural or transcendental.

Example

Philosophers often discuss ultramundane realities beyond human perception.

哲学者たちはしばしば人間の知覚を超えたウルトラムンデインな現実について議論します。

C1 noun /ʌnˈfeɪθfʊlnəs/

unfaithfulness

不貞

Meaning

the quality of being disloyal or not faithful; breach of trust or fidelity

Example

His unfaithfulness led to the end of their marriage.

彼の不貞は結婚の終わりをもたらした。

B2 noun ˌɜːbənaɪˈzeɪʃən

urbanization

都市化

Meaning

The process by which towns and cities are formed and become larger as more people begin living and working in central areas.

Example

Urbanization leads to more developed infrastructure.

都市化はより発展したインフラストラクチャーをもたらす。

C2 adjective /ʌnˈtræməld/

untrammeled

制限のない自由

Meaning

Not restricted or hampered; free and unrestricted.

Example

She enjoyed untrammeled freedom in her new life abroad.

彼女は海外での新しい生活で制限のない自由を楽しんでいた。

B1 adjective /ʌnˈplɛz.ənt/

Unpleasant

不快な

Meaning

not giving or causing pleasure; disagreeable

Example

The medicine had an unpleasant taste.

その薬は不快な味がしました。

B2 adjective /ˌʌnɪnˈfɔːrmd/

uninformed

情報に疎い

Meaning

lacking knowledge or awareness about a particular subject; not educated or informed

Example

The decision was made by an uninformed committee.

その決定は情報に疎い委員会によって下された。

B2 noun /ˈʌndərkləʊðz/

underclothes

下着

Meaning

Clothing worn beneath outer clothes, such as underwear or lingerie

Example

He folded his underclothes neatly before packing them.

彼は下着を丁寧にたたんでから詰めた。

B2 noun /ˈʌpˌkiːp/

up-keep

維持管理

Meaning

The process or cost of maintaining something in good condition.

Example

The upkeep of the old house is very expensive.

古い家の維持管理は非常に高価です。

B2 adjective ʌnˈprɛsɪˌdɛntɪd

unprecedented

前例のない

Meaning

Never done or known before; without previous example.

Example

Unprecedented advancements in science changed human lives.

科学における前例のない進歩は人間の生活を変えました。

B2 adjective /ʌnˈiːvən/

Uneven

不均一; 凹凸のある

Meaning

not level or smooth; not regular or consistent

Example

The road was uneven and full of potholes.

その道は不均一で、穴だらけだった。

B2 noun ˈjuːnəti

unity

団結

Meaning

The state of being united or joined as a whole.

Example

Unity among people led to victory.

人々の団結が勝利をもたらした。

B2 adjective /ʌnˈendɪŋ/

Unending

終わりのない

Meaning

continuing forever; without end

Example

The unending rain made the day feel gloomy.

終わりのない雨が一日を憂鬱にした。

C1 adjective /ʌnˈsɪvəlaɪzd/

Uncivilized

未開の; 野蛮な;

Meaning

not developed in terms of civilization; lacking social organization and culture; barbarous

Example

The explorers encountered an uncivilized tribe deep in the Amazon rainforest.

探検家たちはアマゾンの雨林の奥深くで未開の部族に出会った。

C2 adjective /juːˈʒʊəriəs/

usurious

高利貸しの

Meaning

Charging excessively high interest rates on loans.

Example

The bank was accused of offering loans at usurious rates.

銀行は高利貸しの金利で融資を提供したとして告発されました。

B1 adjective /ʌnˈwel/

Unwell

体調不良; 病気

Meaning

not in good health; feeling sick or ill

Example

She has been feeling unwell since yesterday.

彼女は昨日から体調が悪い。

C1 adjective /ˌʌnrɪˈkwaɪtɪd/

unrequited

Meaning

Not returned or reciprocated, especially in the context of love or affection.

Example

He suffered from unrequited love for years.

C1 adjective /ʌnˈspiːkəbl/

unspeakable

言葉では表現できない

Meaning

too bad or shocking to be expressed in words

Example

The survivors endured unspeakable horrors during the war.

生存者は戦争中に言葉では表現できない恐怖に耐えました。

C2 adjective /ʌpˈrɔːr.i.əs/

uproarious

非常に面白い

Meaning

Extremely funny or noisy; causing loud laughter or commotion.

Example

The comedian's jokes were absolutely uproarious.

コメディアンのジョークは絶対に非常に面白かったです。

C2 adjective /ˌʌltrəˈmɒnteɪn/

ultramontane

教皇支持者

Meaning

beyond the mountains, especially referring to support for the Pope over local church authority

Example

The debate highlighted the ultramontane position in church politics.

その討論は教会政治におけるウルトラモンタンの立場を浮き彫りにした。

C2 noun /ˈʌm.brə/

Umbra

完全な影、太陽黒点の暗い中心

Meaning

the fully shaded inner region of a shadow cast by an opaque object; the dark center of a sunspot

Example

During the eclipse, we stood in the moon's umbra.

日食の際、私たちは月のアンブラの中に立っていました。

B2 adverb /ʌnˈnesəserəli/

Unnecessarily

不必要に

Meaning

to a greater extent than is needed; without necessity

Example

Don't worry unnecessarily about the exam.

試験について不必要に心配しないでください。

B2 adjective /ʌnˌkənˈdɪʃ.ən.əl/

Unconditional

無条件の

Meaning

not subject to any conditions; complete and absolute

Example

She offered her unconditional support to her friend in need.

彼女は困っている友人に無条件のサポートを提供しました。

B1 adjective /ʌnˈfeər/

Unfair

不公平; 不正;

Meaning

not right or just; treating people in a way that favors some over others

Example

It's unfair to blame her for something she didn't do.

それは彼女がやっていないことを責めるのは不公平です。

C1 adjective /ʌnˈtʌtʃəbəl/

Untouchable

触れられない; 批判や攻撃を受けない

Meaning

not able to be touched or affected; beyond criticism or attack

Example

The CEO seemed untouchable despite the scandal.

CEOはスキャンダルにもかかわらず、アンタッチャブルのように見えた。

C2 adjective /ʌkˈsɔːriəs/

uxorious

妻に対して過度に愛情深い

Meaning

excessively fond of or submissive to one's wife

Example

He was so uxorious that he agreed with everything his wife said.

彼は妻に対してそれほどまでに uxorious で、妻が言ったことすべてに同意しました。

C2 verb /ʌnˈfrɒk/

unfrock

神父の職を剥奪する

Meaning

To remove a priest from his position or deprive someone of a rank.

Example

The corrupt priest was unfrocked after the investigation.

腐敗した神父は調査後に職を剥奪されました。

C1 adjective /ʌnˈkʌltʃəd/

Uncultured

無教養な; 教養のない

Meaning

lacking good manners, refinement, or education; uncivilized

Example

His uncultured behavior embarrassed everyone at the dinner party.

彼の無教養な行動はディナーパーティーでみんなを困らせた。

C1 adjective /ˌjuːnɪˈlætərəl/

Unilateral

一方的

Meaning

one-sided; involving only one party

Example

The country made a unilateral decision to withdraw from the treaty.

その国は条約から撤退するという一方的な決定を下しました。

B2 noun /ʌnˈsɜːrtənti/

Uncertainty

不確実性; 疑念または確信の欠如

Meaning

the state of being uncertain; doubt or lack of sureness

Example

The uncertainty about the weather delayed our trip.

天気についての不確実性が私たちの旅行を遅らせた。

B2 adjective /ʌnprɪˈpɛrd/

Unprepared

準備不足

Meaning

not ready or able to deal with something

Example

He was unprepared for the difficult exam.

彼は難しい試験に準備していなかった。

C1 adjective /ˌʌnfɔːrθˈkʌmɪŋ/

unforthcoming

協力的でない

Meaning

Not willing to talk or provide information; uncooperative.

Example

The witness was unforthcoming about what he had seen.

証人は見たことについて協力的でなかった。

B2 adjective /ʌnˈiːzi/

Uneasy

不安な; 心配な; 落ち着かない

Meaning

worried; anxious; uncomfortable; restless

Example

She felt uneasy about walking alone at night.

彼女は夜一人で歩くことに不安を感じていた。

C2 adjective /ʌnˈælɔɪd/

unalloyed

純粋

Meaning

Pure, complete, and not mixed with anything else.

Example

She felt unalloyed joy at the news of her success.

彼女は成功のニュースを聞いて純粋な喜びを感じた。

B1 adjective /ʌnˈʃʊr/

unsure

不確かな

Meaning

not certain or confident; feeling doubt

Example

She felt unsure about the decision.

彼女はその決定について不確かだった。

B2 verb /ˌʌndərˈmaɪn/

undermine

弱める

Meaning

to gradually weaken or damage something or someone

Example

Constant criticism can undermine a child's confidence.

継続的な批判は子どもの自信を弱める可能性があります。

C1 adjective /ʌnˈkɛmpt/

unkempt

だらしない

Meaning

Having an untidy or disheveled appearance.

Example

He looked unkempt after sleeping outdoors all night.

彼は一晩外で寝た後、だらしなく見えた。

B2 adjective /ʌnˈiːkwəl/

Unequal

不平等; 不正;

Meaning

not the same in quantity, size, or value; not fair or just

Example

The distribution of wealth is unequal in many countries.

多くの国々では、富の分配は不平等です。

C1 adjective /ˌʌnəbˈtruːsɪv/

unobtrusive

目立たない

Meaning

not attracting attention; blending in without causing notice

Example

The security cameras are designed to be unobtrusive.

セキュリティカメラは目立たないように設計されています。

A2 noun /ˈjuːnɪt/

unit

ユニット

Meaning

an individual thing or person regarded as a single and complete entity

Example

Each unit in the production line is carefully tested.

生産ラインの各ユニットは慎重にテストされます。

B2 adjective /ʌnhaɪˈdʒiːnɪk/

Unhygienic

不衛生な; 適切な衛生状態の欠如

Meaning

not clean; lacking proper sanitation

Example

The restaurant was closed due to unhygienic conditions in the kitchen.

レストランは不衛生な厨房の状態で閉店しました。

C2 adjective ˌʌn.əˈseɪ.lə.bəl

unassailable

打破できない

Meaning

Unable to be attacked, questioned, or defeated.

Example

An unassailable position ensures dominance.

打破できない位置は支配を確保します。

B2 adjective /ˌʌnˈnoʊ.tɪst/

Unnoticed

気づかれなかった; 無視された

Meaning

not seen or observed; ignored

Example

His hard work went unnoticed by his manager.

彼の努力はマネージャーに気づかれませんでした。

C1 adjective /ˈʌpərˌmoʊst/

uppermost

最上

Meaning

situated at the highest place or most important

Example

Her family's safety was uppermost in her mind during the crisis.

危機の間、彼女の心の中で最も重要なのは家族の安全でした。

C1 adjective /ʌnˈvɔɪst/

unvoiced

未表現

Meaning

not expressed in speech; in phonetics, a sound produced without vocal cord vibration

Example

The student kept her opinion unvoiced during the meeting.

学生は会議中に自分の意見を未表現のままにしておいた。

C1 adjective /ʌnˈruːli/

Unruly

無秩序な; 不従順な;

Meaning

difficult to control or manage; disorderly and disruptive

Example

The unruly crowd refused to follow the safety instructions.

無秩序な群衆は安全指示に従うことを拒否した。

C1 adjective /ʌnˈsəʊʃəbl/

unsociable

非社交的な

Meaning

not enjoying the company of others; avoiding social interaction

Example

He became unsociable after moving to a new city.

新しい街に引っ越してから、彼は非社交的になった。

C2 verb /ʌnˈkaʊtʃ/

uncouch

ソファから取り除く（稀な意味）

Meaning

to remove from a couch or to release from being laid down (rare/archaic usage)

Example

The surgeon attempted to uncouch the cataract.

外科医は白内障を取り除こうとしました。

C1 verb /ʌnˈkɔrk/

uncork

コルクを抜く

Meaning

To remove the cork from a bottle; to open a bottle, especially of wine

Example

He uncorked the wine and poured a glass for everyone.

彼はワインのコルクを抜き、皆にグラスを注いだ。

A2 adjective /ʌnˈkʌmfətəbl/

Uncomfortable

不快

Meaning

causing or feeling physical or emotional discomfort

Example

He felt uncomfortable during the long meeting.

長い会議の間、彼は不快に感じました。

B1 adjective /ʌnˈnoʊn/

Unknown

未知

Meaning

not known or identified; unfamiliar

Example

The author of this letter remains unknown.

この手紙の著者は不明のままです。

B1 adjective /juːˈnaɪtɪd/

United

団結した; 一緒に; 同意した

Meaning

joined together for a common purpose; in agreement

Example

The team was united in their goal to win.

チームは勝利を目指して団結していた。

C1 noun /ˈʌlsər/

ulcer

Meaning

a sore on the skin or a mucous membrane that does not heal easily

Example

The doctor prescribed medicine to treat the stomach ulcer.

C1 noun /ˌʌl.tɪˈmeɪ.təm/

Ultimatum

最終通告

Meaning

a final demand or statement of terms, the rejection of which will result in retaliation

Example

The boss gave him an ultimatum: improve or be fired.

上司は彼に最終通告を与えた：改善するか、解雇されるかだ。