1. a person who commits arson; someone who deliberately sets fire to property

Examples

• The arsonist was caught on security camera lighting the abandoned building.
• Police arrested the suspected arsonist after finding evidence at his home.
• The serial arsonist had set fire to five warehouses in the past month.
• Investigators determined that an arsonist was responsible for the forest fire.
• The arsonist received a ten-year prison sentence for destroying the school.
• Witnesses saw the arsonist fleeing the scene just before the explosion.