Translation guide
Describes a back that is curved or hunched, often due to age, posture, or physical condition. Japanese uses different words for a permanently bent back (like an elderly person's stoop) versus temporarily bending forward (like bowing or leaning).
Describe a back that is chronically curved forward, often associated with old age or poor posture.
Literally 'cat back', this is the most common word for a hunched or rounded back, often from poor posture. It can refer to a temporary slouch or a more permanent stoop.
Medical/technical term for a stooped back, especially in elderly people (kyphosis). More formal than 猫背.
As people age, they often develop a stooped back.
Phrase meaning 'one's back becomes bent', often used for elderly people whose backs have curved with age. Literally 'the waist/back bends'.
My grandmother has a bent back.
More literal phrase meaning 'one's back bends'. Can be used similarly to 腰が曲がる but slightly less common.
As you get older, your back bends.
Describe the action of bending one's back forward, such as when bowing, leaning over, or stooping down.
To bend one's back forward intentionally. Used for bowing deeply or leaning forward.
He bowed deeply, bending his back.
To bend at the waist. Often used when someone stoops or bends forward, e.g., to pick something up.
Bend over to put on shoes.
To lean forward, bending the back. Common in everyday situations like working at a desk or listening closely.
Lean forward and listen.
Describe a back that is arched or bent in the opposite direction (backwards).
猫背 (nekoze) is a general term for a hunched back, often from poor posture, and can be temporary or chronic. 腰が曲がる (koshi ga magaru) specifically describes the age-related bending of the spine, implying a permanent condition. Use 猫背 for slouching, and 腰が曲がる for an elderly person's stoop.
You're young but you have a hunched back.
Grandma has a bent back (from age).
English 'bent back' can be a noun phrase, but in Japanese, you usually need a verb phrase like 背中を曲げる (to bend one's back) or an adjective phrase like 背中が曲がっている (back is bent). Simply saying 曲がった背中 (magatta senaka) is grammatical but less natural for describing a person's posture; it sounds more like a 'bent back' as an object.