The formation of pits on a surface because of corrosion(noun)
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Use "pitting" in a sentence
"I would definitely have your barrel inspected by either the manufacturer or a qualified gun smith if the pitting is very apparent."
"In it, London took a deep pleasure in pitting two "civilized" men -- actually caricatures of such men -- against one another as they are pitted against the harsh realities of pitiless nature."
"Some readers don't care if that's scientific nonsense because, hey, it's coooool and there's a lot of escapist fun to be had in pitting the hero against his own diabolic double: brain out, sponge in, sit back and enjoy the spectacle."