(1):

(n.) The state of being rolled upon itself, or rolled or doubled together; a tortuous or sinuous winding or fold, as of something rolled or folded upon itself.

(2):

(n.) An irregular, tortuous folding of an organ or part; as, the convolutions of the intestines; the cerebral convolutions. See Brain.

(3):

(n.) The act of rolling anything upon itself, or one thing upon another; a winding motion.