Sow's opposite (4)
I believe the answer is:
reap
'sow's opposite' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for reap that I've seen before include "Gather 23dn" , "Harvest (a crop)" , "Harvest, garner" , "Cut or gather (a harvest)" , "Save harvest, glean" .)