Smell masker (9)
I believe the answer is:
deodorant
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">smell masker</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for deodorant that I've seen before include "hum suppressor" , "Antiperspirant" , "Smell masker" , "Substance that removes unwanted smells" , "Underarm protection?" .)