Pianist Serkin (6)
I believe the answer is:
rudolf
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">pianist serkin</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 rudolf that I've seen before include "A popular red-nosed reindeer" , "- Nureyev, twenieth century ballet dancer" , "N Nureyev, dancer" , "One of Santa's reindeer" .)