Longitudinal brace (5)
I believe the answer is:
strut
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">longitudinal brace</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 strut that I've seen before include "Brace - affected gait" , "Walk proudly like peacock" , "Vain walk" , "Walk pompously" , "Reinforcing rod" .)