n.
Function: adjective
Date: 15th century
1 : of, relating to, or involving arson : ARSONOUS
2 : tending to excite or inflame : INFLAMMATORY < incendiary speeches>
3 a : igniting combustible materials spontaneously b : of, relating to, or being a weapon (as a bomb) designed to start fires
4 : extremely hot < incendiary chili peppers>