One can feel pain in guts before death (5,3)
I believe the answer is:
nerve end
'one can feel pain' is the definition.
I don't know anything about this answer so I can't tell whether this works.
'guts before death' is the wordplay.
'guts' becomes 'nerve' (I've seen this in another clue).
'before' says to put letters next to each other.
'death' becomes 'end' (synonyms).
'nerve'+'end'='NERVE-END'
'in' acts as a link.
Can you help me to learn more?
(Another definition for nerve end that I've seen is " Extremity of sensation-transmitting fibre".)