Declare invalid (5)
'declare invalid' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for annul that I've seen before include "Cancel officially" , "Invalidate" , "Countermand" , "Cancel, make void" , "Nullify" .)
'declare invalid' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for nullify that I've seen before include "In fully (anag.)" , "Make void" , "Make invalid" , "Invalidate" , "Declare invalid" .)