Webster’s Revised Unabridged Dictionary · 1913
Bosporian
Bos·po′ri·an, a. [L. Bosporus, G. Βόσπορος, lit., ox-ford, the ox's or heifer's ford, on account of Io's passage here as a heifer; fr. βοῦς ox, heifer + πόρος ford.] Of or pertaining to the Thracian or the Cimmerian Bosporus.
The Alans forced the Bosporian kings to pay them tribute and exterminated the Taurians. Tooke.