The dory or doru (/ˈdɒruː/; Greek: δόρυ) was the chief spear of hoplites (heavy infantry) in Ancient Greece. The word doru is first attested in the Homeric epics with the meanings of "wood" and "spear". Homeric heroes hold two dorata (Greek: δόρατα, plural of δόρυ) (Il. 11,43, Od. 1, 256). In classical antiquity, the dory was a symbol of military power, possibly more important than the sword, as can be inferred from expressions like "Troy conquered by dory" (Il. 16,708) and words like "doryktetos" (Greek: δορίκτητος) (spear-won) and "doryalotos" (Greek: δορυάλωτος) (spear-taken).
The spear used by the Persian army under Darius I and Xerxes in their respective campaigns during the Greco-Persian Wars was shorter than that of their Greek opponents. The dory's length enabled multiple ranks of a formation to engage simultaneously during combat.