The term Caucasoids or Caucasians properly refers to a major race which originates in a geographic area which includes Europe, Northern Africa, and West Asia. This area corresponds to major geographic barriers that made contacts and genetic exchange between different groups difficult: Oceans, the Sahara desert, and the Himalayas mountain range (and the deserts and the mountain ranges bordering on the Himalayas).
The terms derive from the Caucasus Mountains between the Black and Caspian sea. The term Caucasians was introduced in 1795 (in German) by the German anthropologist Johann Friedrich Blumenbach because the supposed ancestral origin lay in this region.
A more correct geographic description of the Caucasoids may be "West Eurasians and North Africans".
Especially in the United States, the term Caucasians may refer exclusively to Europeans.
In Europe, especially in Russia and nearby, Caucasian usually describes exclusively people who are from the Caucasus region or speak the Caucasian languages.
The Caucasoids are composed of smaller groups, such as the Europeans.