What is the meaning of establishment?

noun

• The act of forming or establishing something.
  • usage: "the constitution of a PTA group last year"; "it was the establishment of his reputation"; "he still remembers the organization of the club"
  • synonyms: constitution, formation, organization, organisation
• An organization founded and united for a specific purpose.
  • synonyms: institution
• The persons (or committees or departments etc.) who make up a body for the purpose of administering something.
  • usage: "he claims that the present administration is corrupt"; "the governance of an association is responsible to its members"; "he quickly became recognized as a member of the establishment"
  • synonyms: administration, governance, governing body, brass, organization, organisation
• A public or private structure (business or governmental or educational) including buildings and equipment for business or residence.
• Any large organization.
• Ecology) the process by which a plant or animal becomes established in a new habitat.
  • synonyms: ecesis
• The cognitive process of establishing a valid proof.
  • synonyms: validation