- Atheism a disbelief in the existence of God, or any form of divinity.
- Agnosticism is the view that the existence of God, or any form of divinity is unknowable.
- Apatheism is a non interests in the existence, or non-existence of God, or any form of divinity.
- Anti-clericalism is opposition to religious authority.
- Antireligion is opposition to religion of any kind.
- Antitheism is the opposition to theism.
- Nontheism is a non espoused view of belief in the existence of God, or any form of divinity.
- Irreligion is the absence, indifference to, or rejection of religion.
