Short piece of verse; jingle (5)
I believe the answer is:
rhyme
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">short piece of verse</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >'<span class="explanation-format__original">jingle</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ ></span>
(Other definitions for rhyme that I've seen before include "Correspond in sound" , "Verse, doggerel" , "Short piece of verse" , "'Moon' and 'June' do" , "Box and cox, for example" .)