v To pronounce the sibilant letter ‘s’ imperfectly; to give ‘s’ and ‘z’ the sounds of ‘th’ ((IPA|/θ / ð/)) — a defect common amongst children.
v To speak with imperfect articulation; to mispronounce, as a child learning to talk.
v To speak hesitatingly and with a low voice, as if afraid.
v To pronounce with a lisp.
v To utter with imperfect articulation; to express with words pronounced imperfectly or indistinctly, as a child speaks; hence, to express by the use of simple, childlike language.
v To speak with reserve or concealment; to utter timidly or confidentially; as, to lisp treason.