Mystery, n.; pl. Mysteries.
Etymology: [L. mysterium, Gr. Mute, a.]
1. A profound secret; something wholly unknown, or something kept cautiously concealed, and therefore exciting curiosity or wonder; something which has not been or can not be explained; hence, specifically, that which is beyond human comprehension. We speak the wisdom of God in a mystery. 1 Cor. ii. 7. If God should please to reveal unto us this great mystery of the Trinity, or some other mysteries in our holy religion, we should not be able to understand them, unless he would bestow on us some new faculties of the mind. Swift.
2. A kind of secret religious celebration, to which none were admitted except those who had been initiated by certain preparatory ceremonies; -- usually plural; as, the Eleusinian mysteries.
3. pl.
The consecrated elements in the eucharist.
1 more senses
4. Anything artfully made difficult; an enigma.
1 other Webster entry under this spelling
Mystery, n.; pl. Mysteries.
1. A trade; a handicraft; hence, any business with which one is usually occupied. Fie upon him, he will discredit our mystery. Shak. And that which is the noblest mystery Brings to reproach and common infamy. Spenser.
2. A dramatic representation of a Scriptural subject, often some event in the life of Christ; a dramatic composition of this character; as, the Chester Mysteries, consisting of dramas acted by various craft associations in that city in the early part of the 14th century. "Mystery plays," so called because acted by craftsmen. Skeat.
Shades of meaning
Fernald lists mystery only as an antonym, under revelation.
He lists it without comment; the entries above explain its neighbors.