Lively energy (3)
I believe the answer is:
pep
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">lively energy</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 pep that I've seen before include "Palindrome for vigour" , "Ginger; tax-free investment" , "Palindromic energy or vim" , "Go" , "Palindromic vim and vigour" .)