cachet (n.) Look up cachet at Dictionary.com
1630s, Scottish borrowing of French cachet "seal affixed to a letter or document" (16c.), from Old French dialectal cacher "to press, crowd," from Latin coactare "constrain" (see cache). Meaning evolving through "(letter under) personal stamp (of the king)" to "prestige." Compare French lettre de cachet "letter under seal of the king."