The New Dictionary of Cultural Literacy, Third Edition. 2002.
Neanderthal
(nee-AN-duhr-thawl, nee-AN-duhr-tawl) The ancient and now extinct relatives of modern humans. Neanderthals lived in Europe about 150,000 years ago and were the earliest form of the human species, Homo sapiens.
The term Neanderthal is sometimes used to refer to a person who is thought to have primitive or unenlightened ideas: I tried talking politics to Joe, but hes a real Neanderthal.