What is "combusting"

Usage examples of "combusting".

Now, it is true that combustion can refer to agitation or tumult, but for the purposes of this essay, when I mention combust, combustion, or combusting, I am talking about something or someone burning up.

I look upon my life and I am simply left shaking my head, wondering how I managed to contain all the rage that surged in me without spontaneously combusting or in some other way experiencing an abrupt end.

Would I extinguish myself in the fire, like some spontaneously combusting person?

In his memory he imagined a mindless crawling thing, fleeing the fire like an animal fleeing a combusting forest.