Make one's bones

Common card · No. 470999

To "make one's bones" is an American English idiom meaning to take actions to establish achievement, status, or respect. It is an idiomatic equivalent of "establish[ing] one's bona fides". Although the idiom appears to have originated in the United States criminal underworld, it has since migrated to more popular and less sinister usage; such as discussions of various professions and occupations including law enforcement personnel, the legal profession, and journalists.

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