Trade punches (4)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">trade punches</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for spar that I've seen before include "Box; various minerals" , "Box for practice" , "Box in training - mineral" , "Yard" , "Close friend" .)
(Other definitions for box that I've seen before include "Receptacle" , "Punch" , "Wooden case" , "Engage in pugilism" , "Spar; tree" .)