Webster's Revised Unabridged Dictionary · 1913

aegis

aegis (ē"jis) , noun

[Latin aegis, from Greek a'igi`s a goat skin, a shield, a'i`x goat, or from 'ai`:ssw to rush.]

A shield or protective armor; -- applied in mythology to the shield of Jupiter which he gave to Minerva. Also fig.: A shield; a protection.