Lie in hospital, exhausted (4)
I believe the answer is:
tale
'lie' is the definition.
(as in telling tales)
'in hospital exhausted' is the wordplay.
'in' indicates the answer is hidden within the clue.
'TALE' is hidden within 'hospital exhausted'.
(Other definitions for tale that I've seen before include "Old wives' recital?" , "Yarn or story" , "Shakespeare play: 'The Winter's . . . .'" , "relation" , "Fable" .)