What is the meaning of Set_off?

To leave; to set out; to begin a journey or trip.

To begin; to cause; to initiate.

To cause to explode, let off.

To put into an angry mood; to start (a person) ranting or sulking, etc.

To enhance by emphasizing differences.

To offset, to compensate for: to reduce the effect of, by having a contrary effect.

To deface or soil the next sheet; said of the ink on a freshly printed sheet, when another sheet comes in contact with it before it has had time to dry.

Source: wiktionary.org