Happy nurse, say, almost off duty (8)
I believe the answer is:
carefree
'happy' is the definition.
(synonyms)
'nurse say almost off duty' is the wordplay.
'nurse say' becomes 'carer' (I've seen this in another clue).
'almost' means to remove the last letter (most of the word but not all of it).
'off duty' becomes 'free' (I've seen this in another clue).
'carer' with its final letter removed is 'care'.
'care'+'free'='CAREFREE'
(Other definitions for carefree that I've seen before include "Jaunty" , "Not worried" , "Light-hearted, no worries" , "Free from anxiety or responsibility" , "Without worry or responsibility" .)