The first occurrence.
And God created the great sea creatures, and every living creature that moves, with which the waters swarmed, with regard to their kinds, and every winged creature with regard to its kind; and God saw that it was good. Gen 1:21
The primitive root.
resh ר = head of man, thus head, first, top, beginning, man
mem מ ם = water, thus chaos, mighty, blood
sin ס = thorn, thus grab, hate, protect
The story: The heads of every living thing (resh; we still say, “heads of cattle” when speaking of the herd), when moving together as the waves of the sea (mem) tramples underfoot as thorns trample the earth (sin).