apei·ron | \əˈpīˌrän, -pā-\
plural apeira\-rə, -ˌrä \

Definition of apeiron 

: the unlimited, indeterminate, and indefinite ground, origin, or primal principle of all matter postulated especially by Anaximander

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History and Etymology for apeiron

Greek, from neuter of apeiros endless, infinite, from a- a- entry 2 + -peiron (from peirat-, peirar end, conclusion); akin to peri around

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to reject or criticize sharply

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