Speech problem
I believe the answer is:
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">speech problem</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for lisp that I've seen before include "Slight speech impediment" , "Have difficulty pronouncing `s'" , "speak imperfectly" , "Slip into speech defect" , "peech impediment" .)