Jump on one foot (3)
I believe the answer is:
hop
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">jump on one foot</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 hop that I've seen before include "Skip; beer flavouring ingredient" , "Jump about on one leg" , "Climbing plant - jump!" , "Jump on one foot" , "It's used in brewing" .)