Hey Rampuppy, take a look at Gen. 1: 21, where it says "great sea monsters". If I recall correctly the literal translation of this phrase means "big scaly animal" and can be accurately rendered "giant reptiles"! Also "leviathan" can discribe the Nile Crocodile, now whether you want to call a 20', 3/4 ton monster a dinosaur I will leave to you, Have fun!