- Hetairoi (sing. Hetairos) the name of the Macedonian aristocracy and later Companion cavalry
- Hetairai (sing. Hetaira) female sophisticated companions, courtesans.
- Hetairideia festival of Magnesians and Macedonians.
- Hetairiai or Ancient Greek clubs associations of ancient Greeks who were united by a common interest or goal.
- Hetairia or Andreia the Cretan terms for Doric Syssitia (common meals)
- Hetaireios epithet of Zeus
- Hetaireia Byzantine imperial guard. Hetaireiarches its commander.
- Hetaerism a term employed by 19th-century anthropologists (such as Johann Jakob Bachofen) to indicate a theoretical early state of human society characterized by the absence of the institution of marriage in any form. Women were the common property of their tribe, and the children never knew their fathers.
- Hetaerism also refers to the customs of ancient Greece, particularly those of Classical Athens, according to which a man's wife was forbidden to accompany him to many public events. At such occasions, men sought out the company of courtesans or "Hetaerae" instead.