lisped

Pronunciation:  US [lɪsp] UK 
  • n.Biting tongue sounds; slurred speech, (leaves, water, etc), rustle
  • v.Th s and z, (child) said with slurred speech
  • abbr."Meter" LISP LISP
  • WebLISP (LISt Processor); tongue; Locator ID Separation Protocol
v.
1.
to pronounce something or speak so that " s" and " z" are pronounced like the soft " th" sound in " third" or " thick" 
n.
1.
a minor speech difficulty in which the sounds " s" and " z" are pronounced like the " th" sound 
abbr.