Overly quick (5)
I believe the answer is:
hasty
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">overly quick</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 hasty that I've seen before include "Impulsive" , "Rushed; rash" , "Quick but ill-considered" , "Too hurried, careless" , "Impetuous - quick-tempered" .)