Alluvial - Alluvial soil is rich earth deposited by floods, usually over riverbanks. The Nile flooded annually in summer this way, renewing the fertility of the soil and the Egyptians' ability to grow crops and feed themselves over and over again. Their gratitude for this is reflected in their religion.
Monotheistic - belief in one god only. The Egyptians had one chief god, Amun Re (pronounced 'Rah'). He was their sun god who ruled the whole universe.
Polytheistic - worship of many gods. The Egyptians had hundreds of gods who represented aspects of nature (eg.: Amun Re the male sun god, Khons, his son, the moon god, Horus the hawk-headed god of the sky). There were also gods for the stars, animals, etc., and some were for certain regions only.