Leviathan

Leviathan is a sea monster referenced in the Tanakh, or the Old Testament.

The word has become synonymous with any large sea monster or creature. In literature – e.g., Herman Melville's Moby-Dick – it refers to great whales, and in Modern Hebrew, it simply means «whale». It is described extensively in Job 41 and mentioned in Psalm 104:26 and Isaiah 27:1.