a person who deliberately sets fire to buildings, etc.; pyromaniac; incendiary
firebug in American English
(ˈfaiᵊrˌbʌɡ)
noun
informal
arsonist; incendiary; pyromaniac
Word origin
[1870–75, Amer.; fire + bug1]This word is first recorded in the period 1870–75. Other words that entered Englishat around the same time include: Mafia, asymmetric, billing, fifth wheel, washout
Examples of 'firebug' in a sentence
firebug
Police yesterday arrested two people suspected of starting one of the fires and released a photofit of a suspected firebug.