Stonecutters (6)
I believe the answer is:
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">stonecutters</span>' is the definition.<br/ ><span class="explanation-format__explanation">('mason' can be a synonym of 'stonecutter')</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for masons that I've seen before include "Craftsmen working in stone" , "Stoneworkers - may be free" , "Workers with stone - may be Free" , "They work with stone and brick" .)