/ lɪsp; NAmE / noun , verb
■ noun
[ usually sing. ] a speech fault in which the sound 's' is pronounced 'th' :
She spoke with a slight lisp.
■ verb
[ v , v speech ] to speak with a lisp
••
WORD ORIGIN
Old English wlispian (recorded in āwlyspian ), from wlisp (adjective) lisping, of imitative origin; compare with Dutch lispen and German lispeln .