1911 Encyclopædia Britannica/Apteral

APTERAL (from the Gr. ἄπτερος, wingless, ἀ-, privative and πτερός, a wing), an architectural term applied to amphiprostyle temples which have no columns on the sides; in the Ionic temple on the Acropolis at Athens known as Nike Apteros, the adjective is used, not as applying to the goddess of victory but to the absence of any peristyle on the sides.