Stare with an open mouth (4)
I believe the answer is:
gape
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">stare with an open mouth</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 gape that I've seen before include "Failure to meet" , "Open-mouthed stare" , "Stare stupidly" , "Hang wide open" , "Look open-mouthed" .)