Plow (4)
'plow' is the definition.
(thesaurus)
This is all the clue.
(Other definitions for cultivate that I've seen before include "Grow (crops)" , "Try to get in with" , "Foster" , "Promote" .)
'plow' is the definition.
(I know that plow is a more specific form of the action the till)
This is the entire clue.
(Other definitions for till that I've seen before include "Shop receptacle for cash" , "Cash machine" , "there's money in it" , "store for money" , "Up to (a point in time)" .)