Symbol adopted by Vladivostok entrepreneurs (5)
I believe the answer is:
token
'symbol' is the definition.
(token is a kind of symbol)
'adopted by vladivostok entrepreneurs' is the wordplay.
'adopted by' says the answer is hidden in the clue.
'TOKEN' can be found hidden inside 'vladivostok entrepreneurs'.
(Other definitions for token that I've seen before include "Sign - voucher - chip" , "Money substitute" , "Badge; voucher" , "Nominal; voucher" , "Emblem" .)