Translation guide
The English word 'jaw' refers to the bony structure of the mouth, but in Japanese, the specific term depends on whether you mean the upper jaw, lower jaw, chin area, or the joint. This guide helps learners choose the right word for anatomy, everyday expressions, and idiomatic uses.
Referring to the jaw in a general or anatomical sense, such as when describing its shape, pain, or movement.
The most common and general word for 'jaw' or 'chin'. It can refer to the entire jaw area, but often specifically the lower jaw or chin. Context usually clarifies.
He has a narrow jaw.
My jaw hurts.
Literally 'lower jaw'. Used when you need to be specific about the lower part, often in medical or detailed descriptions.
I broke my lower jaw bone.
Literally 'upper jaw'. Used for the upper part, often in dental or anatomical contexts.
I have pain in my upper jaw.
Medical term for 'jawbone'. Used in clinical settings.
I had jawbone surgery.
When you specifically mean the protruding part of the face below the mouth, often called the 'chin' in English.
Referring to the temporomandibular joint, often in the context of pain or disorders.
The anatomical term for 'jaw joint'. Commonly used in the phrase 顎関節症 (TMJ disorder).
I have TMJ disorder and it's hard to open my mouth.
English idioms like 'jaw-dropping' or 'to jaw' (talk) don't translate directly. Here are natural Japanese equivalents.
Literally 'jaw dislocates', used figuratively for something extremely funny or surprising, similar to 'jaw-dropping' in a laughing sense.
I laughed my head off at that joke.
Describes a gaping mouth in surprise, similar to 'jaw-dropping'. Often used with する or 開ける.
I was left jaw-dropped at the sight.
An onomatopoeic verb for chattering or 'jawing' (talking incessantly). Casual.
She's always jawing away.
Describing the shape or definition of the jaw from an aesthetic perspective.
English speakers sometimes mix up 'jaw' and 'cheek'. In Japanese, 頬 (ほほ/ほお) means cheek, while 顎 (あご) is jaw/chin. Be careful when describing facial features.
Her cheeks are red.
When you say 'my jaw hurts' or 'I hit my jaw', simply use 顎 (あご). It's understood as the lower jaw/chin area unless you specify 上顎 or 下顎. For medical contexts, use the more precise terms.
She walks with her chin up.
下顎を引いてください。
Please tuck your chin in.