- climacteric c.1600 (adj.), 1620s (n.), from L. climactericus, from Gk. klimakterikos "of a critical period," from klimakter "rung of a ladder" (see CLIMAX (Cf. climax)). A critical stage in human life, a period supposed to be especially liable to change. By some, held to be the years that are multiples of 7 (7, 14, 21, etc.), by others only the odd multiples (7, 21, 35, etc.), and by still others the multiples of 9. The Great Climacteric was the 63rd year (7x9), supposed to be especially critical.
Etymology dictionary. 2014.