The hoplite was a heavy infantryman, the central element of warfare in Ancient Greece. The word hoplite (Greek ὁπλίτης, hoplitēs) derives from hoplon (ὅπλον, plural hopla, ὅπλα) meaning an item of armour or equipment, thus 'hoplite ' may approximate to 'armoured man '. Hoplites were the citizen-soldiers of the Ancient Greek City-states. They were primarily armed as spear-men and fought in a phalanx formation.

See Wikipedia - http://en.wikipedia.org/wiki/Hoplite.