Sentence:  In her right hand Minerva bore a beaming lance, and in her left a buckler, called the <WSD>Egis</WSD>. The <WSD>Egis</WSD> of Minerva had embossed upon it the head of Medusa. 
Meaning of the word marked with <WSD> tags:  A mythological shield associated with the Greek deities Zeus and Athena (and their Roman counterparts Jupiter and Minerva) shown as a short cloak made of goatskin worn on the shoulders, more as an emblem of power and protection than a military shield. The aegis of Athena or Minerva is usually shown with a border of snakes and with the head of Medusa in the center. (from early 17th c.)