Amused expression (4)
I believe the answer is:
grin
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">amused expression</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 grin that I've seen before include "11 smile" , "Beam" , "Toothy smile" , "Look pleased" , "A broad smile showing the teeth" .)