FIRE (3)

Fire, v. i. 1. 1. To take fire; to be kindled; to kindle.
2. 2. To be irritated or inflamed with passion.
3. 3. To discharge artillery or firearms; as, they fired on the town.
To fire up, to grow irritated or angry. “He . . . fired up, and stood vigorously on his defense.” Macaulay.