Troglodyte (7)
I believe the answer is:
caveman
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">troglodyte</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I know that caveman is a type of troglodyte)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for caveman that I've seen before include "he has primitive habits" , "Prehistoric male" , "Troglodyte" , "Prehistoric chap" , "old-timer?" .)