Synonyms for Cancel (same or very similar meaning)
WordNet sense 1 (a notation cancelling a previous sharp or flat):
natural
WordNet sense 2 (make up for):
offset, set off
WordNet sense 3 (postpone indefinitely or annul something that was scheduled):
scratch, scrub, call off
WordNet sense 4 (declare null and void; make ineffective):
strike down
WordNet sense 5 (remove or make invisible):
delete
WordNet sense 6 (make invalid for use):
invalidate
From the ODE community, based on WordNet
add/edit