olemus
(1a) tagasiulatuvalt
näiteks ennistama käsu käivitusele eelnenud olekut
Wiktionary:
2. (transitive) to invalidate or annul something.
He cancelled his order on their website

(1b) ennetavalt
näiteks märgistama andmeid nende eiramiseks töötluses
Wiktionary:
3. (transitive) to mark something (such as a used postage stamp) so that it can't be reused
This machine cancels the letters that have a valid zip code.