δελφίς

Greek delphis (δελφίς) is related to delphys (δελφύς), meaning 'womb.' The connection was biological observation: dolphins are mammals that give birth to live young, suckle them with milk, and breathe air. Greek sailors knew this. The dolphin was the animal that was most like a human in the sea — warm-blooded, social, and born from a womb.

Dolphins were sacred in Greek culture. Killing one was punishable by death in some city-states. The myth of Arion — a poet rescued from drowning by dolphins who were charmed by his music — appears in Herodotus (~440 BCE). The oracle at Delphi may take its name from the same root: either the dolphin or the womb, depending on which legend you follow. Apollo was said to have arrived at Delphi in the form of a dolphin.

Latin delphinus passed through Old French daulphin into English dolphin by the 1300s. The French title dauphin (heir to the throne) comes from the same word — the lords of the Dauphine region used a dolphin as their heraldic emblem, and when the last Dauphin sold his lands to the French crown in 1349, the title transferred to the king's eldest son.

Modern research has confirmed what Greek sailors suspected: dolphins are among the most cognitively complex animals on earth. They use names — specific whistle patterns that identify individuals. They teach hunting techniques culturally, not just genetically. They recognize themselves in mirrors. The animal the Greeks named after the womb turned out to have one of the most sophisticated minds in the ocean.