keystone species
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C1 noun ˈkiː.stəʊn ˈspiː.ʃiːz

keystone species

キーストーン種
Meaning
A species on which other species in an ecosystem largely depend, such that if it were removed the ecosystem would change drastically.
Example
Wolves are a keystone species that regulate prey populations.
オオカミは獲物の個体数を調整するキーストーン種です。
A1 noun /ˈkɪtʃən/

Kitchen

キッチン
Meaning
a room or area where food is prepared and cooked
Example
The kitchen was filled with the smell of fresh bread.
キッチンは新鮮なパンの匂いで満たされていた。
B2 noun /ˈkiːɒsk/

kiosk

キオスク
Meaning
A small, open-fronted hut or cubicle from which newspapers, refreshments, tickets, etc., are sold.
Example
She bought a bottle of water from the kiosk near the station.
彼女は駅の近くのキオスクで水のボトルを買いました。
C1 noun /nɒb/

Knob

ドアや引き出しの丸い取っ手; 機械の小さな丸いスイッチ
Meaning
a rounded handle on a door or drawer; a small rounded switch on a machine
Example
He turned the brass knob to open the old wooden door.
彼は古い木の扉を開けるために真鍮のノブを回した。
C2 noun /kəˈbɑːdi/

kabadi

廃品回収業者
Meaning
a person who collects and sells scrap or recyclable materials, especially in South Asia
Example
The kabadi came every week to collect old newspapers and bottles.
廃品回収業者は古い物を集めます。
C2 noun /ˌklɛptəˈmeɪniæk/

kleptomaniac

盗みを抑えきれない衝動を持つ人
Meaning
A person with an irresistible urge to steal, typically without need or profit.
Example
The kleptomaniac was caught shoplifting again.
そのクレプトマニアは再び店で万引きして捕まった。
A2 noun /naɪf/

Knife

ナイフ
Meaning
a cutting instrument with a sharp blade
Example
She used a sharp knife to cut the vegetables for dinner.
彼女は夕食のために野菜を切るために鋭いナイフを使った。
C2 noun /noʊl/

Knoll

小さな丘; マウンド
Meaning
a small rounded hill or mound
Example
The old oak tree stood majestically on top of the grassy knoll.
古いオークの木は、草に覆われた小さな丘の頂上に堂々と立っていました。
A2 verb /kɪs/

Kiss

キス
Meaning
to touch with the lips as a sign of affection
Example
The mother kissed her baby goodnight.
母親は赤ちゃんにおやすみなさいのキスをしました。
A2 verb /kɪd/

kid

冗談を言う
Meaning
to joke or tease; to speak in a playful manner
Example
I'm just kidding with you.
私はただあなたと冗談を言っているだけです。
B1 noun /ˈkɪŋdəm/

Kingdom

王国
Meaning
a country or territory ruled by a king or queen
Example
The kingdom was known for its rich culture and traditions.
その王国は豊かな文化と伝統で知られていた。
A1 noun /kiːp/

Keep

生活費; 城の最強部分
Meaning
food and other things necessary for living; the strongest part of a castle
Example
He worked hard to earn his keep and support his family.
彼は家族を支えるために一生懸命働いた。
C2 noun /noʊl koʊl/

Knol khol

カリフラワー
Meaning
round bulbous vegetable from cabbage family with pale green color and mild taste
Example
Knol khol can be eaten raw in salads or cooked in curries.
カリフラワーはサラダで生で食べることも、カレーにしても美味しいです。
A2 noun /kɪŋ/

King

王
Meaning
the male ruler of an independent state, especially one who inherits the position by right of birth
Example
The king ruled the country with wisdom and fairness.
王は知恵と公正で国を治めました。
B2 verb /nɪt/

knit

編む
Meaning
To make clothes or fabric by interlocking loops of yarn with needles.
Example
She loves to knit scarves for her friends during the winter.
彼女は冬に友達のためにスカーフを編むのが好きです。
C1 noun /ˈkɪləˌwɒt/

kilowatt

キロワット
Meaning
a unit of power equal to 1,000 watts
Example
The generator produces ten kilowatts of electricity.
発電機は10キロワットの電力を生産します。
C2 noun /ˈkɜːrtʃɪf/

kerchief

バンダナ
Meaning
a piece of cloth worn around the head or neck
Example
She wore a red kerchief on her head.
彼女は頭に赤いバンダナを巻いていました。
B1 noun /kɪˈlɒmɪtər/ or /ˈkɪləˌmiːtər/

kilometer

キロメートル
Meaning
a unit of length equal to 1,000 meters
Example
The village is about five kilometers away from the town.
その村は町から約五キロメートル離れています。
C1 verb /niːd/

knead

こねる
Meaning
to work dough or clay into a uniform mixture by pressing, folding, and stretching
Example
She kneads the dough until it becomes smooth.
彼女は生地を滑らかになるまでこねます。
A1 adjective /kaɪnd/

Kind

親切な; 思いやりのある
Meaning
gentle; caring; compassionate; showing sympathy
Example
He is a kind person who always helps others.
彼はいつも他の人を助ける親切な人です。
A2 noun /nɒk/

Knock

ノック; 叩く
Meaning
a sudden sharp blow; the sound of striking something
Example
There was a loud knock at the door late at night.
深夜にドアで大きなノックの音がしました。
C1 noun /ˈken.əl/

Kennel

犬小屋; 犬の繁殖や預かりを行う施設
Meaning
a small shelter for a dog; an establishment for the breeding or boarding of dogs
Example
The dog slept comfortably in his wooden kennel in the backyard.
犬は裏庭の木製のケネルで快適に寝ていました。
C1 noun /ˈkɜːrnəl/

kernel

何かの中心; ナッツや種子の食べられる部分
Meaning
the central, most important part of something; the edible part of a nut or seed
Example
The kernel of the argument was about fairness.
議論の核心は公平についてでした。
B2 verb /niːl/

kneel

ひざまずく
Meaning
to go down on one's knees; to rest on the knees
Example
The knight knelt before the king.
騎士は王の前でひざまずいた。
C1 noun

Kin

家族; 親戚;
C1 noun /ˈkærət/

karat

カラット
Meaning
A unit for measuring the purity of gold, with 24 karats being pure gold.
Example
The ring was made of 18-karat gold.
その指輪は18カラットの金で作られていました。
A2 noun /ˈkiːbɔːrd/

keyboard

キーボード
Meaning
a set of keys used to operate a computer, typewriter, or similar device for inputting text and commands
Example
She typed the report quickly on her keyboard.
彼女はキーボードで素早くレポートを入力した。
C2 noun /ˈkɪləˌliːtər/

kiloliter

キロリットル
Meaning
a unit of capacity equal to 1,000 liters
Example
The tank can hold up to three kiloliters of water.
タンクは最大で3キロリットルの水を保持できます。
B1 noun; gerund /ˈnɪtɪŋ/

knitting

編み物
Meaning
the craft or activity of making fabric by interlocking loops of yarn with needles; the act of forming something closely or firmly together
Example
She spends her evenings knitting scarves for her family.
彼女は家族のために夜に編み物をします。
A2 verb /kɪl/

kill

殺す
Meaning
to cause the death of; to end life
Example
The hunter killed the deer.
ハンターは鹿を殺した。
B1 noun /naɪt/

Knight

騎士; 中世の戦士
Meaning
a man given a rank of honor by a British king or queen; a medieval warrior on horseback
Example
The brave knight rescued the princess from the dragon's castle.
勇敢な騎士はドラゴンの城から姫を助けました。
C2 noun /ˈkɪŋɡlɪŋ/

kingling

小さな王
Meaning
A minor or petty king; a ruler of small importance.
Example
The kingling demanded respect from his people despite his small realm.
その小さな王は、小さな王国にもかかわらず、彼の人々に尊敬を要求しました。
C1 adjective /ˈnæk.ərd/

Knackered

非常に疲れた; くたびれた
Meaning
extremely tired; exhausted
Example
I'm absolutely knackered after working all day.
私は一日中働いた後、完全に疲れ果てました。
A2 noun /ˈkɪndərˌɡɑːrtn/

kindergarten

幼稚園
Meaning
a school or class for young children, typically between the ages of four and six
Example
She enrolled her child in kindergarten to prepare for elementary school.
彼女は子供を小学校に備えて幼稚園に入学させました。
C2 noun /kɛn/

ken

理解の範囲
Meaning
one's range of knowledge or understanding
Example
Quantum physics is beyond my ken.
量子物理学は私の理解を超えています。
C1 noun /kɪˈməʊnoʊ/

kimono

着物
Meaning
a traditional Japanese robe with wide sleeves, tied with a sash
Example
She wore a beautiful silk kimono at the ceremony.
彼女は儀式で美しい絹の着物を着ていた。
B2 verb /ˈkɪdnæp/

kidnap

誘拐する
Meaning
to take someone away illegally by force
Example
The criminals kidnapped the wealthy businessman.
犯罪者は裕福なビジネスマンを誘拐しました。
C1 adjective /kɪˈnɛtɪk/

kinetic

運動エネルギー
Meaning
Relating to or resulting from motion.
Example
Kinetic energy increases as the object moves faster.
物体が速く動くとき、運動エネルギーは増加します。
C2 adjective /ˈkɪŋ.ki/

Kinky

変わった性的習慣; カールした髪
Meaning
having or involving unconventional sexual practices; having tight curls or bends
Example
His kinky hair made him look unique.
彼のくるくるした髪は彼をユニークに見せました。
C1 noun /kəˈlaɪdəˌskoʊp/

kaleidoscope

万華鏡
Meaning
A toy or instrument with mirrors and colored pieces that create changing patterns when rotated; also used metaphorically for a constantly changing sequence of patterns or elements.
Example
The city lights turned into a kaleidoscope of colors as the festival began.
祭りが始まると、街の明かりは色とりどりの万華鏡に変わった。
B2 adjective /ˌkaɪnd ˈhɑːrtɪd/

kind-hearted

優しい
Meaning
Having a kind and generous nature; showing compassion and care for others.
Example
She is known as a kind-hearted teacher who always helps her students.
彼女は常に生徒を助ける優しい教師として知られています。
C2 noun

Kinsfolk

親戚, 家族
C2 noun /ˈkɪldʒɔɪ/

killjoy

空気を壊す人
Meaning
a person who spoils the fun or enjoyment of others
Example
Don’t be a killjoy at the party.
パーティーで空気を壊す人にならないで。
C2 noun /ˈneɪvəri/

knavery

詐欺
Meaning
dishonest or deceitful behavior; trickery
Example
The politician’s knavery was exposed by the media.
政治家の詐欺はメディアによって暴露された。
C2 noun /ˈkɪŋʃɪp/

kingship

王権
Meaning
The position, dignity, or authority of a king.
Example
The king’s advisors often reminded him of the responsibilities of kingship.
王の顧問たちはしばしば彼に王権の責任を思い出させました。
C1 noun /ˈnaɪt.hʊd/

knighthood

騎士の位
Meaning
The rank or dignity of a knight, or the ceremony of conferring knighthood.
Example
He was honored with knighthood for his contributions to science.
彼は科学への貢献で騎士の位を授与されました。
C2 verb /ˌkaʊˈtaʊ/

kowtow

過度に従順である
Meaning
To act in an excessively subservient or obedient manner.
Example
He refused to kowtow to the unreasonable demands.
彼は不合理な要求に従うことを拒否した。
A2 adjective /kəˈriːən/

korean

韓国の
Meaning
relating to Korea, its people, language, or culture
Example
We went to a Korean restaurant for dinner.
私たちは夕食のために韓国のレストランに行きました。
A2 noun /ˈkɪt.ən/

Kitten

子猫
Meaning
a young cat
Example
The little kitten loves to play with yarn balls.
小さな子猫は毛糸の玉で遊ぶのが大好きです。
B1 noun /ˈkiː.wi/

Kiwi

キウイ
Meaning
a small brown fruit with green flesh and black seeds; a flightless bird from New Zealand
Example
I love eating fresh kiwi for breakfast.
私は朝食に新鮮なキウイを食べるのが好きです。
B2 noun

Kitchen garden

キッチンガーデン; キッチンの近くの庭
C2 adjective /ˈnaɪt.li/

Knightly

騎士のような; 高貴で勇敢
Meaning
having the characteristics of a knight; chivalrous; noble and brave
Example
He showed knightly courage in defending the innocent.
彼は無実を守るために騎士のような勇気を示した。
A2 noun /ˈnɒl.ɪdʒ/

knowledge

知識
Meaning
Facts, information, and skills acquired through experience or education.
Example
Knowledge of the universe is expanding through research.
宇宙の知識は研究によって広がり続けています。
B1 noun /ˈkɪlər/

killer

殺人者
Meaning
A person or thing that kills.
Example
The police caught the killer last night.
警察は昨晩殺人者を捕まえた。
C1 verb /ˈkɪndəl/

kindle

灯す
Meaning
to light a fire; to arouse or inspire
Example
She kindled the campfire with dry wood.
彼女は乾いた木でキャンプファイヤーを灯しました。
B2 adjective /ˈnoʊ.ɪŋ/

Knowing

知識; 洞察力; 賢い;
Meaning
showing awareness or understanding; perceptive; shrewd
Example
She gave him a knowing smile when he mentioned the secret.
彼は秘密に言及したとき、彼女は知っているような笑顔を見せた。
C2 noun /ˌkiː.təʊˈdʒen.ɪ.sɪs/

ketogenesis

ケトン生成過程
Meaning
The metabolic process by which the liver produces ketones from fatty acids, providing an alternative energy source during low carbohydrate availability.
Example
Ketogenesis occurs during fasting or low-carb diets.
ケトジェネシスは断食や低炭水化物ダイエット中に発生します。
B2 noun /ˈkiː.pər/

Keeper

守衛; 飼育係;
Meaning
a person whose job it is to guard or take care of something or someone; a goalkeeper
Example
The zoo keeper fed the animals every morning at eight o'clock.
動物園のキーパーは毎朝8時に動物たちに餌を与えていました。
A2 noun /kaɪt/

Kite

ハゲタカ
Meaning
a bird of prey with long wings and a forked tail; also a toy flown in the air
Example
The kite soared high above the fields looking for prey.
凧は田んぼの上で獲物を探しながら高く飛んでいた。
B2 adjective /ˈnɑː.lɪ.dʒə.bəl/

Knowledgeable

知識豊富な; 教養のある; 有識な
Meaning
having extensive knowledge; well-informed; educated
Example
She is very knowledgeable about ancient history.
彼女は古代史に非常に詳しいです。
B1 adjective /kiːn/

Keen

鋭い; 激しい; 熱心
Meaning
sharp; acute; intense; eager
Example
She has a keen interest in science.
彼女は科学に強い関心を持っています。
B2 noun /ˈkɪdni/

Kidney

腎臓
Meaning
either of a pair of organs that filter waste products from the blood and produce urine
Example
Drinking plenty of water helps keep your kidneys healthy.
十分な水分を摂取することで、腎臓の健康を保つことができます。
C1 adverb /ˈnoʊɪŋli/

knowingly

故意に
Meaning
in a way that shows you are aware of something; intentionally
Example
She knowingly kept the secret from her friends.
彼女は故意に友達に秘密を隠しました。
C2 noun /kɪθ/

kith

親しい友人
Meaning
Friends, acquaintances, and relations.
Example
He invited all his kith and kin to the wedding.
彼は結婚式にすべての親しい友人と親戚を招待しました。
C1 noun /næk/

knack

才能
Meaning
a natural skill or ability; a special talent for doing something easily
Example
She has a knack for making people feel comfortable.
彼女には人々を快適に感じさせる才能がある。
A2 adjective /noʊn/

known

知られている
Meaning
recognized or familiar; something that is identified or acknowledged
Example
He is a well-known actor in the country.
彼は国でよく知られた俳優です。
C2 noun /kəˈdʌm.bə/

Kadamba

カダンバの木
Meaning
A tropical tree with round, fragrant orange flowers, sacred in Hindu culture and associated with Lord Krishna
Example
The kadamba tree is mentioned frequently in ancient Indian poetry.
カダンバの木は古代インドの詩で頻繁に言及される。
B2 noun /ˈker.ə.siːn/

Kerosene

ケロシン
Meaning
a combustible hydrocarbon liquid widely used as a fuel in lamps and heating systems
Example
The old lamp burned kerosene to provide light during power outages.
古いランプは停電中に光を提供するためにケロシンを燃やしていました。
C2 noun /neɪv/

Knave

不正直な人；トランプのジャック
Meaning
a dishonest person, especially a man; a playing card with a picture of a male servant
Example
The knave tried to cheat the old woman out of her savings.
その悪党は年老いた女性をだまして、貯金を奪おうとした。
C1 noun /ˈkɪŋ.fɪʃ.ər/

King-Fisher

カワセミ
Meaning
a small bird with bright blue and orange feathers that catches fish by diving into water
Example
The colorful kingfisher dove into the pond to catch a fish.
色とりどりのカワセミが池に飛び込んで魚を捕まえました。
C2 noun /kəˈrɒn.də/

Karonda

カロンダ
Meaning
a small dark purple berry-like fruit that is sour and used in pickles
Example
Karonda is often used to make pickles and preserves.
カロンダは、ピクルスや保存食を作るのによく使われます。
B1 noun

Kindness

親切; 優しさ; 思いやり
B1 noun /ˈkɪləɡræm/

kilogram

キログラム
Meaning
the base unit of mass in the metric system equal to 1,000 grams
Example
The bag of rice weighs five kilograms.
その米袋は五キログラムあります。
A2 noun /ˈketʃ.ʌp/

Ketch-up

ケチャップソース
Meaning
a thick sauce made chiefly from tomatoes, vinegar, and spices
Example
She squeezed some ketchup on her french fries before eating them.
彼女はフレンチフライにケチャップをかけてから食べました。
C2 noun /ˈkedʒ.ə.riː/

Kedgeree

ケジリー
Meaning
a European dish of cooked rice, fish, and hard-boiled eggs, originally from India
Example
The breakfast menu featured traditional kedgeree with smoked haddock and eggs.
朝食のメニューには、スモークハドックと卵が入った伝統的なケジリーがありました。
A2 noun /niː/

Knee

膝
Meaning
the joint connecting the thigh and the lower leg in humans
Example
He fell and scraped his knee on the pavement.
彼は転んで、歩道で膝を擦りむきました。
B2 noun /nɒt/

Knot

結び目
Meaning
a fastening made by tying a piece of string, rope, or something similar; a hard mass in wood
Example
The sailor tied a secure knot to anchor the boat safely.
船乗りはボートを安全に停泊させるためにしっかりとしたノットを結びました。
C2 noun /ˈkɪzmɛt/

kismet

運命
Meaning
Destiny or fate.
Example
Meeting her on that day felt like pure kismet.
その日に彼女に会うことは純粋な運命のように感じました。
C2 noun /kɪln/

kiln

窯
Meaning
a furnace or oven for burning, baking, or drying, especially one for firing pottery or bricks
Example
The potter placed the clay pots into the kiln for firing.
陶芸家は粘土の壺を窯で焼くために置きました。
B2 noun /ˈkɪlɪŋ/

killing

殺人
Meaning
the act of causing death, especially deliberately
Example
The movie depicts the brutal killing of the villagers.
映画は村人たちの残忍な殺人を描いています。
A1 noun /kiː/

Key

鍵
Meaning
a small piece of shaped metal used to operate a lock; something that provides a means of access
Example
She lost her house key and couldn't get inside until the locksmith arrived.
彼女は家の鍵を失くして、鍵屋が来るまで中に入れませんでした。
A1 verb /noʊ/

know

知る
Meaning
to have information about something; to be familiar with
Example
I know the answer to this question.
私はこの質問の答えを知っています。
B1 noun /kɪt/

kit

道具セット
Meaning
a set of tools, equipment, or materials used for a particular purpose
Example
He bought a first aid kit for emergencies.
彼は緊急事態に備えて救急キットを購入しました。
C2 adjective /ˈnɒti/

knotty

複雑
Meaning
Complicated, difficult to solve or full of knots.
Example
He faced a knotty legal issue.
彼は複雑な法的問題に直面しました。
C1 noun /ˈkiːpˌseɪk/

keepsake

記念品
Meaning
An object kept as a reminder of a person, place, or event.
Example
She gave me a small locket as a keepsake of our friendship.
彼女は私たちの友情の記念として小さなロケットをくれました。
A2 noun /ˌkæŋ.ɡəˈruː/

Kangaroo

カンガルー
Meaning
a large marsupial from Australia that moves by hopping on its strong hind legs
Example
The kangaroo jumped high with its joey in its pouch.
カンガルーは、袋の中に子供を入れて高く跳ねました。
B1 adverb; adjective /ˈkaɪndli/

kindly

親切に
Meaning
in a kind or gentle manner; showing kindness or goodwill
Example
She kindly helped the old man cross the street.
彼女は親切に老人が道を渡るのを手伝った。
C1 noun, adjective /ˈkɪndrəd/

kindred

幸せ
Meaning
A person's relatives or family; similar in nature or character.
Example
They discovered kindred spirits in each other.
彼女は賞を受け取ったとき、自分の幸せを隠すことができませんでした。
A2 noun /ˈket.əl/

Kettle

やかん
Meaning
a container used for boiling water, typically with a lid, spout, and handle
Example
The electric kettle whistled when the water reached boiling point.
電気ケトルは水が沸騰点に達したときに笛のような音を立てました。
C2 noun /nɛl/

knell

鐘の音
Meaning
The sound of a bell, especially when rung solemnly for a death or funeral; a signal of the end or failure of something.
Example
The knell of the church bell echoed through the valley at dusk.
教会の鐘の音が夕暮れ時に谷を響き渡った。
C1 noun /ˈkuːdɒs/

kudos

賛辞
Meaning
Praise and honor received for an achievement.
Example
She received kudos for her excellent performance.
彼女は素晴らしいパフォーマンスで賛辞を受けた。
C2 noun /ˈnɪk.næk/

knickknack

幸福
Meaning
A small decorative object, especially in a house.
Example
The shelf was full of little knickknacks collected from their travels.
彼女は賞を受け取ったとき、喜びを隠すことができませんでした。
B1 noun /kɪk/

Kick

キック; 足で蹴る
Meaning
a blow or forceful thrust with the foot; a sudden strong feeling of excitement
Example
The soccer player scored a goal with a powerful kick from outside the penalty area.
サッカー選手はペナルティエリアの外から強力なキックでゴールを決めました。