Recurring idea (5)
I believe the answer is:
theme
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">recurring idea</span>' is the definition.<br/ ><span class="explanation-format__explanation">(recurring idea or image in a creative work)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for theme that I've seen before include "Subject (of talk, text, etc)" , "Short melody" , "basis for variations" , "A subject or repeated melody" , "Topical item" .)