Cancel, annul (7)
I believe this clue is a double definition.
'cancel' is the first definition.
(I've seen this before)
'annul' is the second definition.
(I've seen this in another clue)
(Other definitions for undo that I've seen before include "Wreck" , "Unfasten - destroy" , "Loosen; cancel" , "Ruin or loose" , "Cause to become loose" .)
I believe this is a double definition.
'cancel' is the first definition.
(to rescind is to cancel or repeal)
'annul' is the second definition.
(I know that annul can be written as rescind)
(Other definitions for rescind that I've seen before include "Revoke (order)" , "Cancel (regulation)" , "Withdraw (decree)" , "undo" , "Scrub" .)
I believe this is a double definition.
'cancel' is the first definition.
(I know that revoke is a more specific form of cancel)
'annul' is the second definition.
(I know that annul can be written as revoke)
(Other definitions for revoke that I've seen before include "(In card games) fail to follow suit" , "Annul (a decree)" , "Annul by recalling" , "Officially cancel a decree" , "Annul (a decree/decision)" .)