lɪsp n. & v. --n. 1 a speechdefect in which s is pronounced like th in thickand z is pronounced like th in this. 2 a rippling of waters; a rustling of leaves. --v.intr. & tr. speak or utter with a lisp. øølisper n. lispingly adv. [OE wlispian (recorded in awlyspian) f. wlisp (adj.) lisping, of uncert. orig.]