- inaudible (adj.)
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- c. 1600, "unable to be heard," from Late Latin inaudibilis "inaudible," from in- "not" (see in- (1)) + audibilis (see audible). Used in Middle English in the sense "unfit to be heard" (mid-15c.). Related: Inaudibly. Classical Latin had inauditus "unheard, unheard of."