Translation guide
The English word "threadbare" has two main uses: describing worn-out fabric, and describing an argument, excuse, or idea that is weak and unconvincing. Japanese uses different expressions for each.
Describing clothing, carpets, or fabric that is so old or overused that the threads are visible or it is about to tear.
The most common and natural way to say threadbare for fabric. Literally 'worn through by rubbing'. Used for clothes, towels, carpets, etc.
彼のジャケットは擦り切れて穴が開いていた。
His jacket was threadbare and had holes in it.
Specifically for clothing that has become threadbare from being worn many times. Emphasizes long use.
Describing an argument, excuse, story, or idea that is weak, unconvincing, or overused to the point of being ineffective.
Means 'lacking persuasiveness'. The most direct and common way to say an argument is threadbare.
彼の言い訳は説得力がなかった。
His excuse was threadbare.
Avoid directly translating 'threadbare' as '糸がむき出しの' (threads exposed) or similar literal phrases. They sound unnatural in Japanese. Use the expressions above depending on context.
It's a threadbare sweater, but it's still warm.
Means worn down or worn thin, often for soles of shoes or carpets. Can be used for fabric that has become thin.
すり減ったカーペットを交換した。
We replaced the threadbare carpet.
Literally 'the fabric has become thin'. A more descriptive phrase, less idiomatic but clear.
このシャツは生地が薄くなって透けて見える。
This shirt is so threadbare you can see through it.
Literally 'full of holes'. Used for arguments or stories that have many flaws or inconsistencies.
その理論は穴だらけだ。
That theory is threadbare.
Means 'worn-out from overuse', similar to a cliché. Used for ideas or expressions that have become stale.
彼のジョークはいつも使い古されている。
His jokes are always threadbare.
Means 'thin, flimsy, shallow'. Can describe an excuse or argument that lacks substance.
そんな薄っぺらい言い訳は通じないよ。
Such a threadbare excuse won't work.