A very rough sea; fun but dangerous (6)
I believe the answer is:
unsafe
'dangerous' is the definition.
(associated in meaning)
'a very rough sea fun' is the wordplay.
'sea fun' can be anagrammed to 'UNSAFE'.
However, I am not clear how this is indicated.
'but' acts as a link.
Can you help me to learn more?
(Other definitions for unsafe that I've seen before include "Precarious" , "Unreliable" , "Hazardous" , "Dangerous - legally without basis" , "Not reliable, dangerous - perhaps a legal conviction" .)