n. The act of involving, infolding, or inwrapping; a rolling or folding in or round.n. The state of being entangled or involved; complication.n. Something involved or entangled; a complication.n. A membranous covering or envelop; an involucre.n. In grammar, complicated construction; the lengthening out of a sentence by the insertion of member within member; the separation of the subject from its predicate by the interjection of matter that should follow the verb or be placed in another sentence.n. In mathematics: The multiplication of a quantity into itself any number of times, so as to produce a positive integral power of that quantity.n. The raising of a quantity to any power, positive, negative, fractional, or imaginary. In this sense involution includes evolution as a particular case.n. A unidimensional continuous series of elements (such as the points of a line), considered as having a definite one-to-one correspondence with themselves, such that infinitely neighboring elements correspond to infinitely neighboring elements, and such that if A corresponds to B, then B corresponds to A: in other words, the elements are associated in conjugate pairs, so that any pair of conjugate elements may by a continuous motion come into coincidence with any other without ceasing, at any stage of the motion, to be conjugate.n. Any series of pairs of loci represented by an equation λU + µ V = 0, where λ and µ are numerical constants for each locus, and U = 0 and V = 0 are equations to two loci of the same order.n. Any unidimensional continuum of elements associated in sets of any constant number by a continuous law. According as there are two, three, four, etc., in each set, the involution is said to be quadratic, cubic, quartic (or biquadratic), etc.n. The implication of a relation in a system of other relations.n. In physiology, the resorption which organs undergo after enlargement or distention: as, the involution of the uterus, which is thus restored to its normal size after pregnancy.n. The atrophic or regressive changes occurring in old age.n. In biology, the possession by an organism which is adapted to conditions that are simpler than those under which its allies live, of an organization that is simpler than that of its allies, considered as evidence of inverse or retrograde evolution.
