Immortal primarily sees death as a blessing (7)
I believe the answer is:
godsend
'a blessing' is the definition.
(I've seen this in another clue)
'immortal primarily sees death' is the wordplay.
'immortal' becomes 'god' (synonyms).
'primarily' suggests taking the first letters.
'death' becomes 'end' (synonyms).
The initial letter of 'sees' is 's'.
'god'+'s'+'end'='GODSEND'
'as' is the link.
(Other definitions for godsend that I've seen before include "Stroke of good fortune" , "Boon - blessing" , "Very helpful thing" , "Dog's den (anag.)" , "welcome acquisition" .)