Henry in literature showing signs of pain (8)
I believe the answer is:
writhing
'showing signs of pain' is the definition.
The definition and answer can be both to do with motion as well as being present participle verbs.
Maybe there's an association between them I don't understand?
'henry in literature' is the wordplay.
I cannot quite see how this works, but
'henry' could be 'h' (symbol for the unit of electrical inductance) and 'h' is found within the answer.
'in' is found in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for writhing that I've seen before include "Showing acute embarrassment" , "Squirming in pain" , "Evincing pain" .)