Noun

1. A state of nature; conformity to nature.
2. Metaphaphoric: The doctrine that denies a supernatural agency in the miracles and revelations recorded in the Bible, and in spiritual influences
3. Any system of philosophy which refers the phenomena of nature as a blind force or forces acting necessarily or according to fixed laws, excluding origination or direction by an intelligent will.
4. A doctrine which denies a strong separation between scientific and philosophic methodologies and/or topics
5. A movement in theatre, film, and literature that seeks to replicate a believable everyday reality, as opposed to such movements as Romanticism or Surrealism, in which subjects may receive highly symbolic, idealistic, or even supernatural treatment.