Drink of vodka at openings in Russian ballet company (5)
I believe the answer is:
kirov
'russian ballet company' is the definition.
(I've seen this in another clue)
'drink of vodka at openings' is the wordplay.
'drink' becomes 'kir' (I've seen this before).
'at openings' indicates taking the first letters (I've seen 'at opening' mean this).
The first letters of 'of vodka' is 'ov'.
'kir'+'ov'='KIROV'
'in' is the link.
(Other definitions for kirov that I've seen before include "Russian dancers" , "Russian city and ballet company" , "Soviet city" , "Famous ballet" , "former ballet company" .)