What was the term for the massive units formed by Greek citizen-soldiers?

Phalanxes were the term used to describe the massive units formed by Greek citizen-soldiers, particularly during the Classical period. This military formation was characterized by tightly-packed rows of soldiers, known as hoplites, who stood shield-to-shield and fought with long spears and large round shields. The phalanx allowed Greek armies to present a solid wall of defense, making it formidable in battle.

The significance of the phalanx lies in its role in Greek military strategy. Because each soldier depended on the man beside him for protection, this formation fostered a sense of unity and discipline among citizens, which was essential for the success of Greek city-states in battles such as those fought during the Persian Wars.

In contrast, other terms like "centuries" and "legions" are associated with the Roman military structure. Centuries were smaller units within the Roman army that formed part of a larger cohort, while legions referred to a larger grouping of soldiers. Squadrons typically refer to units in naval or aerial contexts, rather than land-based infantry formations like those of the Greeks. Thus, phalanxes distinctly highlight the unique military organization of Greek citizen-soldiers.