Translation guide
The English phrase "be sharp" can refer to physical sharpness, mental acuity, punctuality, or even a musical note. This guide breaks down these meanings and provides natural Japanese equivalents.
Describing an object that can cut or pierce easily.
General adjective for sharpness of edges, points, or senses. Can also mean 'keen' or 'acute'.
このナイフは鋭い。
This knife is sharp.
Specifically describes the cutting performance of a blade. Literally 'cutting taste is good'.
この包丁は切れ味がいい。
This kitchen knife is sharp.
Means 'pointed' or 'sharp' for tips, like a pencil or needle. Can also describe a person's sharp tongue.
鉛筆が尖っている。
The pencil is sharp.
Describing a person who is clever, perceptive, or quick to understand.
Common phrase meaning 'smart' or 'intelligent'. Literally 'head is good'.
彼はとても頭がいい。
He is very sharp.
Slang for being sharp-witted or highly capable. Often used for someone who is exceptionally smart or competent.
あの人は切れる。
That person is sharp.
Can also describe mental sharpness, like keen insight or a sharp question.
Describing someone who arrives or does something exactly at the agreed time.
Means 'punctual' or 'precise about time'. A natural way to describe someone who is always on time.
彼は時間に正確だ。
He is sharp (punctual).
Literally 'protect time', meaning to be punctual or keep to a schedule.
彼女はいつも時間を守る。
She is always sharp (on time).
Describing someone who looks fashionable or well-groomed.
Common word for 'stylish' or 'fashionable'. Can be used for both appearance and fashion sense.
彼はいつもおしゃれだ。
He always looks sharp.
Means 'cool' or 'good-looking'. Often used for a sharp, attractive appearance.
そのスーツ、かっこいいね。
That suit looks sharp.
Describing a musical note that is a semitone higher than the natural note.
The loanword シャープ is used for musical sharps. Attach to note names (e.g., Cシャープ).
この音はCシャープだ。
This note is C sharp.
The English 'sharp' as in '9 o'clock sharp' does not translate directly to 鋭い. Use 時間に正確だ or 時間を守る for punctuality, or say 9時ちょうど for 'exactly 9 o'clock'.
切れる is slangy and implies exceptional ability, often in a specific field. 鋭い is more about keen perception or insight. 頭がいい is the safest, most general term for intelligence.
彼の質問は鋭い。
His question is sharp.