1. a miniature representation of something, especially a unit, group, or place regarded as a copy of a larger one; a little world; a world in miniature; a miniature form that represents a larger reality.
2. Philosophy: a) a person regarded as epitomising the universe. b) human beings, humanity, society, or the like, viewed as an epitome or miniature of the world or universe.
3. anything that is regarded as a world in miniature.
Etymology: Middle English microcosme < Mediaeval Latin mīcrocosmus < Greek mīkròs kósmos - small world.