1650s (adj.); 1660s (n.), in grammar, from Late Latin encliticus, from Greek enklitikos "throwing its accent back," literally "leaning on," from verbal adjectival stem of enklinein "to bend, lean on," from en "in" (see en- (2)) + klinein "to lean" (see lean (v.)).[enclitic etymology, enclitic origin, 英语词源]