Sikorsky or Stravinsky (4)
I believe the answer is:
igor
This clue is a double definition.
'sikorsky' is the first definition.
(I've seen this in another clue)
'stravinsky' is the second definition.
(as in the composer Igor Stravinsky)
(Other definitions for igor that I've seen before include "Card game" , "Prince in Borodin's opera" , "Stravinsky, perhaps" , "Prince of grand opera" , "-- Stravinsky, composer" .)