What is another word for one who sets fires illegally?
Pronunciation: [wˈɒn hˌuː sˈɛts fˈa͡ɪ͡əz ɪlˈiːɡə͡li] (IPA) 
Synonyms for the term "one who sets fires illegally" include "pyromaniac," "arsonist," "firebug," "incendiary," "torch," and "fire starter." Pyromaniacs have an obsessive desire to start fires, while arsonists deliberately set homes, buildings, or wildland areas ablaze. Firebugs have a propensity for playing with fire and igniting small fires, often without regard for the danger they pose to others. Incendiary is a broader term that generally refers to a person, weapon, or device that causes fires. The term "torch" is used to describe someone who sets fires for financial gain, such as for insurance purposes. Fire starters are individuals who intentionally set fires for various reasons, such as attention, revenge, or excitement.
