Wiktionary
preheating
vb. (present participle of preheat English)
Usage examples of "preheating".
The oven was preheating and a large springform pan had already been buttered and floured.
From watching that man's torch, from the color of the flame and other indications, I gather that he uses a flame of atomic oxygen-atomic hydrogen for melting, and surrounds it with a preheating jacket of atomic hydrogen.
We keep the fire burning so we don’t have to spend time preheating the kiln.