What is the meaning of adoption?

noun

• The act of accepting with approval; favorable reception.
  • usage: "its adoption by society"; "the proposal found wide acceptance"
  • synonyms: acceptance, acceptation, espousal
• A legal proceeding that creates a parent-child relation between persons not related by blood; the adopted child is entitled to all privileges belonging to a natural child of the adoptive parents (including the right to inherit. )
• The appropriation (of ideas or words etc) from another source.
  • usage: "the borrowing of ancient motifs was very apparent"
  • synonyms: borrowing