Meet order to be abundant (4)
I believe the answer is:
teem
'be abundant' is the definition.
(I've seen this in another clue)
'meet order' is the wordplay.
'order' indicates anagramming the letters.
'meet' with letters rearranged gives 'TEEM'.
'to' acts as a link.
(Other definitions for teem that I've seen before include "Abound - pour" , "Bucket down" , "Pullulate" , "pelt" , "Be prolific" .)