One lacking courage (6)
I believe the answer is:
coward
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">one lacking courage</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 coward that I've seen before include "Person who shows fear or timidity" , "Scaredy-cat" , "Person who is deficient in courage" , "Gutless type" , "Poltroon" .)