Lose vitality being awfully liverish when one passes out (7)
I believe the answer is:
shrivel
'lose vitality' is the definition.
I can't explain the rest of the clue.
(Other definitions for shrivel that I've seen before include "Shrink as from cold" , "Wrinkle and contract" , "Desiccate" , "Contract into wrinkles" , "Wither, shrink" .)