Urges one to become bountiful (8)
I believe the answer is:
generous
'bountiful' is the definition.
('generous' can be similar in meaning to 'bountiful')
'urges one to become' is the wordplay.
'to become' indicates anagramming the letters.
'urges'+'one'='urgesone'
'urgesone' with letters rearranged gives 'GENEROUS'.
(Other definitions for generous that I've seen before include "Lavish" , "Charitable" , "Munificent; liberal" , "Showing largess" , "Benevolent, big-hearted" .)