Compete to get in Riviera (3)
I believe the answer is:
vie
'compete' is the definition.
(synonyms)
'to get in riviera' is the wordplay.
'to get' indicates a hidden word.
'VIE' can be found hidden inside 'in riviera'.
(Other definitions for vie that I've seen before include "Compete (with others)" , "I've got to contend" , "Contend, compete" , "Strive in French way?" , "Jockey" .)