indicate the level to which a name has been verified.
Meaning & History
From the name of a town and municipality in Basque Country, Spain, possibly derived from the nearby Roman town Oiasso (also called Oiarso), the name of which may have been applied to the entire surrounding region. The modern spelling is likely influenced by Basque oihartzun "echo", or by oihan "wild forest, rough terrain" and the abundance suffix -tzu.