- Give rise to or cause something to occur. 2. Cause to explode. 3. Distinguish or contrast. 4. Enhance or make more attractive. 5. Begin a journey.
Examples:
- The acid set off a chemical reaction.
Origin: Early 1600s (senses 1, 4); late 1800s (sense 2); late 1500s (sense 3); second half of 1700s (sense 5)
Synonyms: trigger, detonate, set out, depart