Composer of "The Merry Widow" (5)
I believe the answer is:
lehar
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">composer of the merry widow</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for lehar that I've seen before include "Operettist" , "Musician" , "Viennese composer" , "He scored" , "Operetta composer" .)