The definition of a gaffe is something that you say that causes you to feel embarrassed, such as a social blunder or a faux pas.(noun)
When you say something that is socially improper, this is an example of a gaffe.
See gaffe in Webster's New World College Dictionary
Origin: Fr < OProv gaf: see gaff
See gaffe in American Heritage Dictionary 4
Origin: , from Old French, hook; see gaff1.
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