Irritable, quarrelsome (5)
I believe the answer is:
testy
<span class="explanation-format__ClueExplanation">I believe this clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">irritable</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(testy can mean irritable or annoyed)</span><br/ ><br/ >'<span class="explanation-format__original">quarrelsome</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ ></span>
(Other definitions for testy that I've seen before include "likely to flare up?" , "Irascible" , "Bad-tempered" , "Showing irritation" , "Irritably impatient" .)