To call off something (or call something off) is to cancel a planned event, or an event that has already started.
a) They are calling off the tennis match because of the rain.
b) They called off their wedding.
c) Mike is ill so we will have to call the party off.
d) News headline: Spain airport strike called off.
e) The police called off their search for the burglar after they found him hiding in a shed.
f) The Bahrain Grand Prix has been called off.
2. To call off somebody or something (or call somebody or something off) is to give a command to somebody or something (e.g. a dog) to leave someone alone, or to stop attacking someone.
a) Call off your dog!
b) The General called off his troops.
c) OK, I agree to your demands. You can call your lawyers off now.
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