Under fire, poet almost died (7)
I believe the answer is:
shelled
'under fire' is the definition.
(fired at with shells)
'poet almost died' is the wordplay.
'poet' becomes 'shelley' (Percy Bysshe Shelley 1792-1822).
'almost' means to remove the last letter (most of the word but not all of it).
'died' becomes 'd' (abbreviation next to the year of someone's death).
'shelley' with its last letter taken away is 'shelle'.
'shelle'+'d'='SHELLED'
(Other definitions for shelled that I've seen before include "Deprived of casing" , "Under cannon fire" , "Bombed" .)