n. (pl. -ies) 1 a secret, hidden, or inexplicable matter (the reason remains a mystery). 2 secrecy or obscurity (wrapped in mystery). 3 (attrib.) secret, undisclosed (mystery guest). 4 the practice of making a secret of (esp. unimportant) things (engaged in mystery and intrigue). 5 (in full mystery story) a fictional work dealing with a puzzling event, esp. a crime (a well-known mystery writer). 6 a a religious truth divinely revealed, esp. one beyond human reason. b RC Ch. a decade of the rosary. 7 (in pl.) a the secret religious rites of the ancient Greeks, Romans, etc. b archaic the Eucharist. make a mystery of treat as an impressive secret. mystery play a miracle play. mystery tour (or trip) a pleasure excursion to an unspecified destination.
[ ME f. OF mistere or L mysterium f. Gk musterion, rel. to MYSTIC ]