verb

1. To cross out something with lines etc.

2. To invalidate or annul something.

   “He cancelled his order on their website.”

3. 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.”

Synonyms: blacklist, belay, take care of

adjective

1. No longer planned or scheduled.

   “The cancelled show would have drawn 5,000 fans.”

2. (of a mail item) Marked over the stamp, to show that the stamp has been used.