set off
(leave, start a journey or trip)
- I’ll set off early for work.
- They set off for Paris.
(cause a situation or series of events to happen)
- The announcement set off a wave of protests.
- The outbreak of war set off widespread panic.
(to make a bomb explode)
- Terrorists set off a bomb in a crowded shopping center.
- We set off firecrackers to celebrate the Fourth of July.
(to cause an alarm system to operate)
- The cat set the alarm off on the car.
- Your cellphone may set a metal detector off.
- Smoke from a cigarette sometimes set off a smoke detector.