Number upset after dinner maybe without a fruit (5)
I believe the answer is:
melon
'fruit' is the definition.
(melon is a kind of fruit)
'number upset after dinner maybe without a' is the wordplay.
'number' becomes 'no' (abbreviation for 'number'**).
'upset' says the letters should be written backwards.
'after' is a charade indicator (letters next to each other).
'dinner maybe' becomes 'meal' (I've seen this in other clues).
'without' is a deletion indicator.
'no' back-to-front is 'on'.
'meal' with 'a' removed is 'mel'.
'on' put after 'mel' is 'MELON'.
(Other definitions for melon that I've seen before include "Edible gourd" , "Killing" , "Type of fruit" , "Large vine fruit" , "Ogen or cantaloupe, for instance" .)