Our online medical glossary of medical terms and definitions includes definitions for terms related to treatment, and general medicine
1. The state of being out or beyond; separateness.
2. The state or characteristic of being distanguishable from the perceiving mind, by being in space, and possessing marerial characteristic; externality; objectivity. "The outness of the objects of sense." (Sir W. Hamiltom)
Source: Websters Vocabulary