Canst thou draw out leviathan with an hook? The word leviathan, or more properly livyathan, which has previously occurred in Job 3:8, and is found also in Psalms 74:14; Psalms 104:26; and Isaiah 27:1, seems to be derived from לוי, "twisting," and תן, "a monster," whence the תּנּין or תּנּים of the Pentateuch and also of Job (Job 7:12), Jeremiah (Jeremiah 9:11), and Ezekiel (Ezekiel 29:3).
It is thus a descriptive epithet rather than a name, and has not unnaturally been used to designate more than one kind of animal. The best modern critics regard it as applied sometimes to a python or large serpent, sometimes to a cetacean, a whale or grampus, and sometimes, as hero, to the crocodile.
This last application is now almost universally accepted. The crocodile was fished for by the Egyptians with a hook, and in the time of Herodotus was frequently caught and killed (Herod; 2:70); but probably in Job's day no one had been so venturous as to attack him.
Or his tongue with a cord which thou lettest down? rather, or press down his tongue with a cord? (see the Revised Version); i.e. "tie a rope round his lower jaw, and so press down his tongue." Many savage animals are represented in the Assyrian sculptures as led along by a rope attached to their mouths.