Her name literally means female of throne, i.e. Queen of the throne. Her original headdress was an empty throne chair belonging to her murdered husband, Osiris. As the personification of the throne, she was an important source of the Pharaoh's power. Her cult was popular throughout Egypt, but the most important sanctuaries were at Giza and at Behbeit El-Hagar in the Nile delta.

The hieroglyph for her name originally used meant (female) of flesh, i.e. mortal, and she may simply have represented deified, real, queens. The most commonly used name for this deity, Isis, is a Greek corruption of the Egyptian name; and its pronunciation as eye-sis is a further corruption by English speakers.

The true Egyptian pronunciation is unknown, as Egyptian hieroglyphs only recorded consonants, and left out most of the vowels. The Egyptian hieroglyphics for her name are commonly transliterated as jst; as a convenience, Egyptlogists pronounce that as ee-set.

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