Bell or whistle (5)
I believe the answer is:
frill
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">bell or whistle</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 frill that I've seen before include "Unnecessary embellishment" , "Gathered strip as a trimming" , "Ruff, adornment" , "Pleated strip of cloth trimming or an unnecessary extra" , "A decorative gathering of fabric" .)