Soprano interrupting tap dancing in polished comedy (9)
I believe the answer is:
slapstick
'comedy' is the definition.
(slapstick is a kind of comedy)
'soprano interrupting tap dancing in polished' is the wordplay.
'soprano' becomes 's' (musical abbreviation).
'interrupting' indicates putting letters inside.
'dancing' indicates an anagram.
'in' means one lot of letters goes inside another.
'polished' becomes 'slick' (I've seen this before).
'tap' is an anagram of 'apt'.
's' going into 'apt' is 'apst'.
'apst' going into 'slick' is 'SLAPSTICK'.
(Other definitions for slapstick that I've seen before include "That's laughable" , "Knockabout farce" , "Knockabout comedy based on action rather than words" , "unsophisticated humour" , "Unsubtle comedy" .)