Buttonless garment
I believe the answer is:
tee
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">buttonless garment</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 tee that I've seen before include "Mark" , "Drive off it, half-tittering" , "Golf starting point" , "Golf peg" , "Part of course" .)