Chomping at the bit
I believe the answer is:
eager
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">chomping at the bit</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for eager that I've seen before include "Alert and active type?" , "Low platform" , "Agree (anag.)" , "Keenly interested" , "Fervent" .)