'Sea' in the Bible

Daniel said, “I saw in my vision by night, and behold, the four winds of heaven were stirring up the great sea (the nations).

And four great beasts, each different from the other, were coming up out of the sea [in succession].

His body also was like beryl [with a golden luster], his face had the appearance of lightning, his eyes were like flaming torches, his arms and his feet like the gleam of burnished bronze, and the sound of his words was like the noise of a multitude [of people or the roaring of the sea].