Fainted as a result of error in viral illness (9)
I believe the answer is:
collapsed
'fainted' is the definition.
The answer and definition can be both related to bodily activities as well as being past participle verbs.
Maybe there's a link between them I don't understand?
'error in viral illness' is the wordplay.
'error' becomes 'lapse' (lapse is a kind of error).
'in' means one lot of letters goes inside another.
'viral illness' becomes 'cold' (cold is a kind of illness. I am not sure about the 'viral' bit.).
'lapse' inserted inside 'cold' is 'COLLAPSED'.
'as a result of' acts as a link.
Can you help me to learn more?
(Other definitions for collapsed that I've seen before include "Cracked up - gave way" , "laid low" , "Fell apart" , "Gave way, caved in" .)