Main force of a blow (5)
I believe the answer is:
brunt
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">main force of a blow</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for brunt that I've seen before include "Major force" , "Principal strength" , "Chief impact (of something bad) (bear the -)" , "Main force of a blow" , "Burden" .)