Caveman is the slang term for neanderthals. They are early humans who relied almost entirely on the wilderness around them for commodities.
In The Adventures of Ook and Gluk: Kung-Fu Cavemen From the Future, they inhabit a small town called Caveland.
A group of cavepeople also appear in Captain Underpants and the Revolting Revenge of the Radioactive Robo-Boxers when George and Harold are teleported to the plains of Africa, where they teach them English through drawing and invent the world's first comic in the process. The cavepeople then retaliate against Supa Mega Tippy Tinkletrousers and eventually are saved after Captain Underpants makes them warm up inside the fabric of Slightly Younger Tiny Tippy's robot trousers.