Large sea wave and a hair-curler (6)
I believe the answer is:
roller
'large sea wave and a hair-curler' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for roller that I've seen before include "Sea wave; brilliant bird" , "Bright bird; cylinder" , "Long heavy sea-wave" , "Big wave or hair setter" , "Rotating cylinder" .)