A land animal that eats grass like an ox and is not moved by a river in flood.
Behemoth gets the chapter before Leviathan. It eats grass, its strength is in its loins, it lies under the lotus in the marsh, and a river rushing at its mouth does not alarm it. The one line that resists every identification is the tail, which the text likens to a cedar. The hippopotamus fits the habitat and the diet; the elephant fits the bulk; neither fits the tail, which is why the reading that it is a creature of the poem rather than of the riverbank has never gone away.
Disputed. The hippopotamus is the commonest identification, with the elephant next. Both founder on the tail "like a cedar" in Job 40:17, which some read as figurative and some as decisive against a known animal.