Long band of colour (6)
I believe the answer is:
stripe
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">long band of colour</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 stripe that I've seen before include "Military mark of rank, chevron" , "Sign of a soldier's rank" , "Braid showing military rank" , "Band of colour - 3 of rank" , "bar" .)