Origin: 1275–1325; Middle English solem(p)ne (< Old French ) < Late Latin sōlennis, sōlempnis,Latin sōlemnis, variant of sollemnis consecrated, holy, derivative of sollus whole
late 13c., from O.Fr. solempne (Fr. solennel), from L. sollemnis "formal, ceremonial, traditional," perhaps related to sollus "whole" (see safe (adj.). Solemnize is recorded from late 14c.