The first occurrence.
And God called the dry land Earth; and the gathering together of the waters He called Seas: and God saw that it was good. Gen 1:10
The primitive root.
Strong’s H3220 ים yam, a concrete noun meaning, “seas;” from an unnamed, unused primitive root meaning, “to roar.” The pictographs for the noun are yud + mem.
yud י = the closed hand, thus work, throw, worship
mem מ ם = the water, thus chaos, mighty, blood
The story: Working (yud) water (mem), as the water of the sea is always moving.