Sailor changed date and relaxed (6)
I believe the answer is:
abated
'relaxed' is the definition.
(I've seen this before)
'sailor changed date' is the wordplay.
'sailor' becomes 'ab' (abbreviation for able seaman).
'changed' is an anagram indicator.
'date' is an anagram of 'ated'.
'ab'+'ated'='ABATED'
'and' is the link.
(Other definitions for abated that I've seen before include "Relaxed" , "Slacked off, died away" , "Went down and calmed like stormed" , "weakened" , "Lowered" .)