n.
Pronunciation: ˌ in-v ə - ' lü-sh ə n
Function: noun
Etymology: Latin involution-, involutio, from involvere
Date: circa 1611
1 a (1) : the act or an instance of enfolding or entangling : INVOLVEMENT (2) : an involved grammatical construction usually characterized by the insertion of clauses between the subject and predicate b : COMPLEXITY , INTRICACY
2 : EXPONENTIATION
3 a : an inward curvature or penetration b : the formation of a gastrula by ingrowth of cells formed at the dorsal lip
4 : a shrinking or return to a former size
5 : the regressive alterations of a body or its parts characteristic of the aging process <skeletal involution due to loss of estrogens at menopause>
– in · vo · lu · tion · al \ -shn ə l, -sh ə -n ə l \ adjective