[1] : The Collaborative International Dictionary of English v.0.48

lisp \lisp\ li^sp, v. i. imp.  p. p. lisped li^spt;
   p. pr.  vb. n. lisping. oe. lispen, lipsen, as. wlisp
   stammering, lisping; akin to d.  ohg. lispen to lisp, g.
   lispeln, sw. laumspa, dan. lespe.
   1. to pronounce the sibilant letter s imperfectly; to give s
      and z the sound of th; -- a defect common among children.
      1913 webster

   2. to speak with imperfect articulation; to mispronounce, as
      a child learning to talk.
      1913 webster

            as yet a child, nor yet a fool to fame,
            i lisped in numbers, for the numbers came. --pope.
      1913 webster

   3. to speak hesitatingly with a low voice, as if afraid.
      1913 webster

            lest when my lisping, guilty tongue should halt.
                                                  --drayton.
      1913 webster
see also:
lisped lisping 

Lisped >> L Words
Lisped, definition of term: Lisped
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