anything that is kept secret or remains unexplained or unknown

the mysteries of nature.

any affair, thing, or person that presents features or qualities so obscure as to arouse curiosity or speculation

The masked guest is an absolute mystery to everyone.

a novel, short story, play, or film whose plot involves a crime or other event that remains puzzlingly unsettled until the very end

a mystery by Agatha Christie.

obscure, puzzling, or mysterious quality or character

the mystery of Mona Lisa's smile.

any truth that is unknowable except by divine revelation.

(in the Christian religion)

a sacramental rite.

the Eucharist.

an incident or scene in connection with the life of Christ, regarded as of special significance

the mysteries of the Passion.

any of the 15 events in the lives of Christ and the Virgin Mary meditated upon during the recitation of the rosary.

mysteries,

ancient religions that admitted candidates by secret rites and rituals the meaning of which was known only to initiated worshipers.

any rites or secrets known only to those initiated

the mysteries of Freemasonry.

(in the Christian religion) the Eucharistic elements.

mystery play.

noun

known , understanding

noun

abstruseness , brainteaser , braintwister , charade , chiller , cliffhanger * , closed book , conundrum , crux , cryptogram , difficulty , enigma , grabber , inscrutability , inscrutableness , mindboggler , mystification , occult , oracle , perplexity , poser , problem , puzzlement , question , rebus , riddle , rune , secrecy , sixty-four-thousand-dollar question * , sphinx , stickler , stumper , subtlety , teaser , thriller , tough nut to crack , twister , whodunit , why * , puzzle , puzzler , arcanum , cliffhanger , craft , intricacy , novel , secret , story , trade