Noun

1. Worship of the Devil.
2. Any religion seen as both non-Christian and anti-Christian.
3. A profession, philosophy, or ideological construct featuring a positive, admirable, or useful association to the figure, character or entity known as 'Satan'.
4. The religion of the Church of Satan, founded in 1966 by Anton Szandor LaVey, which characterizes human instincts and desires as "Satan" and urges capitulation to such instincts and desires; also called LaVeyan Satanism.

Usage notes

• Satanism is not always capitalized in all senses.
• Self-identified Satanists typically use the term Satanism in senses 2-4, and use the terms Satanic and Satanist analogously.