the.com/pyromaniac

A pyromaniac feels an uncontrollable urge to set fires, a recognized impulse-control disorder, not a rational choice.

means Someone with an uncontrollable, recurring urge to set fires, driven by compulsion and fascination with flame rather than profit, revenge, or any rational motive.

from Built from Greek pyr, 'fire' (the root also behind pyre and pyrotechnics), fused with mania, 'madness' or 'frenzy.' The compound emerged in 19th-century medical and psychiatric language, as doctors were busy coining a whole family of '-mania' disorders — kleptomania, dipsomania — to name compulsions that seemed to seize the will rather than serve any ordinary purpose.

vs arsonist
arsonists want insurance money, pyromaniacs want the feeling
actual rarity
true pyromania is clinically rare, most fire-setters aren't it
the tell
tension before, relief or pleasure after, not profit motive
word origin
greek pyr fire plus mania madness, coined 19th century
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