The correct spelling for the plural of "aegis" is "egises". The word "aegis" comes from Greek mythology and originally referred to the shield of Zeus or Athena. In English, it means protection, support, or backing. The pronunciation of "egises" is /ˈiːdʒɪsiːz/ with the emphasis on the first syllable, and the final "-es" is pronounced as /ɪz/. While the spelling of "egises" may seem unusual, it follows the standard rule for pluralizing nouns ending in "-is".