Apply to (5)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">apply to</span>' is the definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for refer that I've seen before include "Send or direct to a specialist" , "Direct elsewhere" , "Mention/allude (to)" , "Mention, cite" , "Freer (anag.)" .)