Roars (7)
I believe the answer is:
bellows
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">roars</span>' is the definition.<br/ ><span class="explanation-format__explanation">('bellow' can be a synonym of 'roar')</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for bellows that I've seen before include "sings very loudly" , "Device that blows a strong current of air" , "Wind pump; shouts" , "Roars at part of the organ" , "Air blower for fire" .)