mutilation, n. maim, [dismemberment], [mangling].
mutinous, a. [rebellious], insubordinate, [seditious], [insurgent], insurrectionary.
mutiny, n. insurrection, [rebellion], insubordination, [revolt].
mutter, v. maunder.
muttering, a. inarticulate, indistinct, maundering.
mutual, a. reciprocal.
mutuality, n. correlation, reciprocation, [interchange].
muzzle, v. [restrain], [repress].
mysterious, a. [inscrutable], [cryptic], [obscure], [unexplainable], enigmatical, unfathomed, [unfathomable], [abstruse], [mystic], inexplicable, [recondite], cabalistic, [occult], unexplained.
mystery, n. [secret], enigma, [riddle], [intricacy], arcanum.