Expressive, song-like (7)
I believe the answer is:
lyrical
<span class="explanation-format__ClueExplanation">This clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">expressive</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >'<span class="explanation-format__original">song-like</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ ></span>
(Other definitions for lyrical that I've seen before include "Using poetic language, wax thus (7)" , "Highly enthusiastic" , "Song-like, imaginative or expressive" , "We may wax this" , "Relating to song's words" .)