海鷂魚[ei] ray (fish)
井の中の蛙大海を知らず[inonakanokawazutaikaiwoshirazu] parochial
一天四海[ittenshikai] the world
雲海[unkai] sea of clouds
沿海[enkai] coast

遠海[enkai] deep sea
黄海[koukai] Yellow Sea
温海[atsumi] warm sea
海の幸[uminosachi] seafood

金利鞘[kinrishou] interest margin
元鞘[motosaya] returning to normal after all is said and done
朱鞘[shuzaya] red-lacquered sword sheath
腱鞘[kenshou] sheath of tendon
腱鞘炎[kenshouen] inflammation of a tendon (sheath)

値鞘[nezaya] margin
鞘当て[sayaate] rivalry (in love, touching of sheaths)
逆鞘[gyakuzaya] (discount rate) negative spread
鞘取り[sayatori] brokerage