See a rogue relax (4)
I believe the answer is:
ease
'relax' is the definition.
(I've seen this before)
'see a rogue' is the wordplay.
'rogue' indicates an anagram (letters go rogue).
'see'+'a'='seea'
'seea' is an anagram of 'EASE'.
(Other definitions for ease that I've seen before include "Allay" , "Freedom from pain or anxiety" , "Calm" , "Become less severe; facilitate" , "State of relaxation or rest" .)