corporation n.

mid-15c., corporacioun, "persons united in a body for some purpose," from such use in Anglo-Latin, from Late Latin corporationem (nominative corporatio) "assumption of a body" (used of the incarnation of Christ), noun of action from past-participle stem of Latin corporare "embody, make or fashion into a body," from corpus (genitive corporis) "body, dead body, animal body," also "a whole composed of united parts, a structure, system,community, corporation, political body, a guild" (from PIE root *kwrep- "body, form, appearance").

Meaning "legally authorized entity, artificial person created by law from a group or succession of persons" (such as municipal governments and modern business companies) is from 1610s.