Out at elbows. Shabbily dressed (applied to men only), metaphorically, short of money; hackneyed; stale; thus, we say of a play which has been acted too often that it is worn out at elbows. It is like a coat which is no longer presentable, being out at the elbows.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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