κροκόδειλος

Greek krokodeilos combines krokos (pebble, stone) and deilos (worm or small creature). Herodotus used the word in his Histories (5th century BCE) describing his observations in Egypt: a lizard-like creature that basked on Nile stones. The Greek soldiers were likely naming what they saw — a creature as grey-brown as the river pebbles, motionless enough to be mistaken for stone.

The Egyptians called the creature sobek — their crocodile god — and the animal was simultaneously worshipped and feared along the Nile. Crocodile cult centers existed at Kom Ombo and Crocodilopolis (Faiyum), where sacred crocodiles wore gold jewelry and were mummified at death. The Greeks who arrived with Alexander found a religious tradition for the creature they called pebble-worm.

Latin borrowed krokodeilos as crocodilus, which English received as crocodile in the 13th century. The phrase 'crocodile tears' appears in English writing by 1400 — based on the ancient belief that crocodiles wept while eating their prey. The belief is partially true: crocodiles do produce eye secretions while eating, probably for lubrication, not emotion.

The saltwater crocodile (Crocodylus porosus) is the world's largest living reptile, reaching 6 meters and 1,000 kilograms. It is the only animal with the jaw force to pierce a sea turtle's shell. The pebble-worm of Herodotus's Nile has been the same creature for 200 million years — nearly unchanged since before mammals existed.