Wordnet 3.0
NOUN (1)
1. 
 a bomb that is designed to start fires; 
 is most effective against flammable targets (such as fuel); 
[syn: incendiary bomb, incendiary, firebomb]
VERB (1)
1.  attack with incendiary bombs; 
- Example: "The rioters fire-bombed the stores"
WordNet (r) 3.0 (2006):
firebomb
    n 1: a bomb that is designed to start fires; is most effective
         against flammable targets (such as fuel) [syn: incendiary
         bomb, incendiary, firebomb]
    v 1: attack with incendiary bombs; "The rioters fire-bombed the
         stores"