Sound of a snicker (6)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">sound of a snicker</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for tee-hee that I've seen before include "laughing sound" , "A tittering laugh" , "Sound of a titter" , "Derisive giggle" , "Titter, giggle" .)