From WordNet (r) 3.0 (2006) [wn]:
call off
v 1: postpone indefinitely or annul something that was
scheduled; "Call off the engagement"; "cancel the dinner
party"; "we had to scrub our vacation plans"; "scratch that
meeting--the chair is ill" [syn: cancel, call off,
scratch, scrub]
2: give the calls (to the dancers) for a square dance [syn:
call, call off]