What is the meaning of Phalanx?

An ancient Greek and Macedonian military unit that consisted of several ranks and files (lines) of soldiers in close array with joined shields and long spears.

A Fourierite utopian community; a phalanstery.

A large group of people, animals or things, compact or closely massed, or tightly knit and united in common purpose.

One of the bones of the finger or toe.

phalanx, battalion

Source: wiktionary.org