Polabian

[ poh-lah-bee-uh n, -ley- ]
/ poʊˈlɑ bi ən, -ˈleɪ- /

noun

a member of a Slavic people who once lived in the Elbe River basin and on the Baltic coast of northern Germany.
the extinct Slavic language of this people.
Also Po·lab [poh-lahb] /poʊˈlɑb/.

Origin of Polabian

1865–70; Polab + -ian; compare German polabisch, New Latin Polabicus; ultimately from tribal name, formed with common W Slavic po- along, bordering + Lab(a) Elbe River (compare Czech Labe)