Consciousness

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Consciousness is a concept with no one clear definition. It is often used to describe the presence of multiple simultaneous independent streams of thought within one body (as with polyconscious), or even the presence of multiple conscious/sentient agents within one body (as with multiplicity in general). It may also describe the level of awareness a headmate has of the outerworld, as is indicated by co-conscious.

Definitions
definitions may be added here with origin (and references)