Definition of: lisp

(lisp) noun
1. A speech defect or affectation in which the sibilants (s) and (z) are pronounced with the tongue between the teeth so that the sounds produced are like (th) in thank and (th) in this.
2. The act or habit of speaking with a lisp.
3. The sound of a lisp.
—v.t. & v.i.
1. To pronounce or speak with a lisp.
2. To speak imperfectly or in a childlike manner. [OE wlispian]
—lisp′er noun