Devitalize (3)
'devitalize' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for sap that I've seen before include "Undermine the tree juice" , "Imbecile" , "Fluid in plant stem" , "Vital plant juice" , "One is easily fooled" .)
'devitalize' is the definition.
(I know that devitalize is a more specific form of the action the weaken)
This is all the clue.
(Other definitions for weaken that I've seen before include "Relent" , "Lessen the strength of" , "Show signs of giving in" , "Reduce in strength" , "flag" .)