Apa itu lisp? Apa itu lisp? A speech defect or mannerism characterized by mispronunciation of the sounds (s) and (z) as (th) and (th).A sound of or like a lisp: "The carpenter['s] . . . plane whistles its wild ascending lisp” ( Walt Whitman). To speak with a lisp.To speak imperfectly, as a child does.To pronounce with a lisp.