thalassocrat

thal·as·soc·ra·cy

T0139700 (thăl′ə-sŏk′rə-sē)n. pl. thal·as·soc·ra·cies Naval or commercial supremacy on the seas.
[Greek thalassokratiā : thalassa, sea + -kratiā, -cracy.]
tha·las′so·crat′ (thə-lăs′ə-krăt′) n.

thalassocrat

(θəˈlæsəˌkræt) nsomeone who dominates the sea