Finery, Sunday best (4,4)
I believe the answer is:
glad rags
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">finery</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(both can mean formal clothing)</span><br/ ><br/ >'<span class="explanation-format__original">sunday best</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(both can mean fancy clothes)</span><br/ ><br/ ></span>
(Other definitions for glad rags that I've seen before include "What partygoers showed up in" , "Dressy clothes in happy shreds" , "Special kit" , "Smart clothes (for a special occasion)" , "Best bib and tucker" .)