Prim, demure, or affectedly modest; unwilling to speak freely.
From Middle English 'mim,' possibly from Old English or Germanic roots meaning 'to mime' or 'to be silent,' appearing in Chaucer's works.
This is a delightfully obscure word that perfectly captures that irritating quality of false modesty—the kind of person who acts scandalized but probably isn't, and it's barely used anymore because we've developed other ways to mock that behavior.
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