The
phalanx (, ; plural
phalanxes or
phalanges; Ancient and Modern Greek: ) was a
rectangular mass military formation, usually composed entirely of
heavy infantry armed with
spears,
pikes,
sarissas, or similar
weapons. The term is particularly (and originally) used to describe the use of this formation in
Ancient Greek warfare, although the ancient Greek writers used it to also describe any massed infantry formation, regardless of its equipment, as does
Arrian in his
Array against the Alans when he refers to his legions. In Greek texts, the phalanx may be deployed for battle, on the march, even camped, thus describing the mass of infantry or cavalry that would deploy in line during battle. They marched forward as one entity. The word phalanx is derived from the Greek word
phalangos, meaning
finger.