Translation guide
The English word 'thumb' refers to the short, thick first digit of the human hand. In Japanese, the word is 親指 (おやゆび), literally 'parent finger'. This guide covers how to refer to the thumb in various contexts, including body parts, gestures, and idiomatic expressions.
Referring to the thumb as a part of the hand.
The standard word for 'thumb'. Literally 'parent finger', it is the most common and neutral term.
親指を怪我しました。
I injured my thumb.
親指の爪が長いですね。
Your thumbnail is long.
A technical or medical term for 'thumb', often used in anatomy or formal contexts. Rare in everyday speech.
拇指の骨折と診断されました。
I was diagnosed with a fracture of the thumb.
Describing the gesture of approval or 'good job' made with the thumb.
Literally 'to raise one's thumb', this is the standard way to describe giving a thumbs-up.
彼は親指を立てて「いいね」と言った。
He gave a thumbs-up and said 'Nice'.
The English loanword 'thumbs-up', used in casual contexts, especially among younger people or in media.
写真を撮るとき、みんなでサムズアップした。
When we took the photo, everyone did a thumbs-up.
Using the thumb for pressing, holding, or manipulating objects.
Pattern meaning 'to press something with one's thumb'. Replace ～ with the object.
親指でボタンを押してください。
Please press the button with your thumb.
Pattern for 'to pinch with thumb and index finger'. Common when describing fine motor actions.
親指と人差し指で小さな部品をつまんだ。
I picked up the small part with my thumb and index finger.
English idioms involving 'thumb' and their natural Japanese equivalents.
Equivalent to 'rule of thumb' in the sense of a sudden realization or enlightenment. Literally 'scales fall from one's eyes'.
Not a direct translation of 'rule of thumb'. Use this for the 'aha moment' meaning.
その説明を聞いて、目から鱗が落ちた。
When I heard that explanation, it was like a lightbulb moment (literally: scales fell from my eyes).
The closest equivalent to 'rule of thumb' as a practical guideline based on experience. A formal term.
経験則として、毎日30分運動するのが良い。
As a rule of thumb, it's good to exercise for 30 minutes every day.
A more casual term for a rough guideline or standard, similar to 'rule of thumb'.
To suck one's thumb, often used for children. The verb しゃぶる means 'to suck'.
子供が親指をしゃぶっている。
The child is sucking their thumb.
Loanword for 'green thumb' (talent for gardening). Not widely used; often explained as 植物を育てる才能.
彼女は本当にグリーンサムだね。
She really has a green thumb.
In Japanese, 指 (ゆび) means 'finger' in general, but the thumb is specifically 親指. Avoid using 指 alone when you mean thumb, as it may cause confusion.
親指が痛い。
My thumb hurts.
The big toe is called 足の親指 (あしのおやゆび), literally 'foot's parent finger'. In casual speech, it's often just 親指 when context is clear, but specifying 足の avoids ambiguity.
足の親指をぶつけた。
I stubbed my big toe.
As a rule of thumb, please take this medicine three times a day.