Allergic rhinitis (3,5)
I believe the answer is:
hay fever
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">allergic rhinitis</span>' is the definition.<br/ ><span class="explanation-format__explanation">(hay fever is a kind of allergic rhinitis)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for hay fever that I've seen before include "Coward created this" , "Allergic affliction" , "Pollinosis" , "Heavy ref with sneezing ailment" , "Seasonal rhinitis" .)