Labrys is the term for a symmetrical doubleheaded axe originally from Crete in Greece, one of the oldest symbols of Greek civilization.
The first written use of the word labrys comes from Plutarch describing it as a Lydian word for axe:
Herakles, having slain Hippolyte and taken her axe away from her with the rest of her arms, gave it to Omphale. The kings of Lydia who succeeded her carried this as one of their sacred insignia of office, and passed it down from father to son until it was passed to Candaules, who disdained it and gave it to one of his companions to carry.
When Gyges rebelled and was making war upon Candaules, Arselis came with a force from Mylasa to assist Gyges; Arselis then slew Candaules and his companion and took the axe to Caria with the other spoils of war. And, having set up a statue of Zeus, Arselis put the axe in his hand and invoked the god, “Labrandeus”.