Stomach has morning range (5)
I believe the answer is:
gamut
'range' is the definition.
(gamut can mean a range or variety)
'stomach has morning' is the wordplay.
'stomach' becomes 'gut' (I've seen this in another clue).
'has' indicates putting letters inside.
'morning' becomes 'am' (as in 12:00 AM).
'gut' placed around 'am' is 'GAMUT'.
(Other definitions for gamut that I've seen before include "Complete range (of something)" , "Full range, compass" , "Entire scope" , "Ambit" , "Full extent" .)