Severe pain (5)
'severe pain' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for anguish that I've seen before include "Severe mental suffering" , "Severe pain, physical or mental" , "Grief" , "Severe mental distress" , "Angst" .)
'severe pain' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for agony that I've seen before include "Distress" , "Suffering - anguish" , "woe" , "Torture" , "Extreme suffering - kind of aunt" .)