Seen in show, lethargic bird (5)
I believe the answer is:
owlet
'bird' is the definition.
(owlet is a kind of bird)
'seen in show lethargic' is the wordplay.
'seen in' indicates the answer is hidden within the clue.
'OWLET' can be found hidden inside 'show lethargic'.
(Other definitions for owlet that I've seen before include "Little nocturnal bird" , "Young nocturnal flier" , "Wise baby bird?" , "Baby nocturnal raptor" , "Wise young" .)