General bitten by snake, dead to the world (6)
I believe the answer is:
asleep
'dead to the world' is the definition.
(I've seen this before)
'general bitten by snake' is the wordplay.
'general' becomes 'Lee' (Robert E. Lee - US revolutionary commander).
'bitten by' is an insertion indicator (I've seen this in other clues).
'snake' becomes 'asp' (asp is a kind of snake).
'lee' placed inside 'asp' is 'ASLEEP'.
(Other definitions for asleep that I've seen before include "Please (anag) - numb" , "In the arms fo Morpheus" , "Having nodded off" , "Dormant; inattentive" , "in bed?" .)