An ethic group can be defined as a group of people with common language,culture and ancestor while a tribal group can be defines as a group of people with similar speak similar languages.

A dialect can be defined as the language spoken by an ethnic group while a [tribal] language can be be defined as as that which is spoken by a tribal group.

The origin of a people is fixed and set absolutely in stone whereas the identity of any people is never fixed and quite changeable.

A people's origin is usually determined at birth while the identity of most people is usually determined by other people.
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