I got illuminated during discussion of drain (10)
I believe the answer is:
debilitate
'drain' is the definition.
(synonyms)
'i got illuminated during discussion' is the wordplay.
'got' says to put letters next to each other.
'illuminated' becomes 'lit' (synonyms).
'during' means one lot of letters goes inside another.
'discussion' becomes 'debate' (debate is a kind of discussion).
'i'+'lit'='ilit'
'ilit' put within 'debate' is 'DEBILITATE'.
'of' acts as a link.
(Other definitions for debilitate that I've seen before include "Weaken" , "Make very weak" .)