Metal suit (6)
(Other definitions for armour that I've seen before include "Protective body-plating" , "Protection for a fighter" , "Greave, sallet and cuirass are pieces of this" , "Protective covering for battle" , "Protective metal covering for combat" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">metal suit</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 armor that I've seen before include "US military vehicles" , "protection in America" .)