microcosm
n//ˈmaɪ.kɹə(ʊ)ˌkɒz.əm//mikrokosmos
Human nature or the human body as representative of the wider universe; man considered as a miniature counterpart of divine or universal nature. [from 15th c.]
A smaller system which is seen as representative of a larger one. [from 17th c.]
(ecology) A small natural ecosystem; an artificial ecosystem set up as an experimental model. [from 19th c.]