noun ae·gis \ˈē-jəs also ˈā-\
variants: or less commonly

Definition of aegis

  1. 1 :  a shield or breastplate emblematic of majesty that was associated with Zeus and Athena

  2. 2a :  protection under the aegis of the Constitutionb :  controlling or conditioning (see 2condition 5a) influence passed new laws under the aegis of national security

  3. 3a :  auspices, sponsorship under the aegis of the museumb :  control or guidance especially by an individual, group, or system under the aegis of the government

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Examples of aegis in a sentence

  1. having no claim to the land under the aegis of the law, the cattle baron decided to claim it by force

  2. a medical study that was questioned by many because it was done under the aegis of a major pharmaceutical company

Did You Know?

We borrowed "aegis" from Latin, but the word ultimately derives from the Greek noun aigis, which means "goatskin." In ancient Greek mythology, an aegis was something that offered physical protection. In some stories, it was the thundercloud where Zeus kept the thunderbolts he used as weapons. In others, the aegis was a magical protective cloak made from the skin of the goat that had suckled Zeus as an infant. The word first entered English in the 16th century as a noun meaning "shield" or "protection," and by the 20th century it had acquired the extended senses of "auspices" or "sponsorship."

Origin and Etymology of aegis

Latin, from Greek aigis, literally, goatskin, from aig-, aix goat; akin to Armenian ayc goat

First Known Use: 15th century

AEGIS Defined for English Language Learners


noun ae·gis \ˈē-jəs also ˈā-\

Definition of aegis for English Language Learners

  • : the power to protect, control, or support something or someone

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capable of being understood in two ways

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