Wikipedia
Katepano
The katepánō (, lit. "[the one] placed at the top", or " the topmost") was a senior Byzantine military rank and office. The word was Latinized as capetanus/catepan, and its meaning seems to have merged with that of the Italian "capitaneus" (which derives from the Latin word "caput", meaning head). This hybridized term gave rise to the English language term captain and its equivalents in other languages (Capitan, Kapitan, Kapitän, El Capitán, Il Capitano, Kapudan Pasha etc.)