WordNet sense 1 (a response of body tissues to injury or irritation; characterized by pain and swelling and redness and heat):

redness, rubor

WordNet sense 2 (the state of being emotionally aroused and worked up):

excitation, excitement, fervor, fervour

WordNet sense 3 (arousal to violent emotion):

inflaming

WordNet sense 4 (the act of setting something on fire):

ignition, kindling, lighting, firing