A body of heavy-armed infantry formed in ranks and files close and deep. There were several different arrangements, the phalanx varying in depth from four to twenty-five or more ranks of men.
- A compact or close-knit body of people: "formed a solid phalanx in defense of the Constitution and Protestant religion” ( G.M. Trevelyan).
- A formation of infantry carrying overlapping shields and long spears, developed by Philip II of Macedon and used by Alexander the Great.
- Anatomy A bone of a finger or toe. Also called phalange.
- See phalanstery.