What is the meaning of co-opt?

verb

• Choose or elect as a fellow member or colleague.
  • usage: "The church members co-opted individuals from similar backgrounds to replenish the congregation"
• Neutralize or win over through assimilation into an established group.
  • usage: "We co-opted the independent minority tribes by pulling them into the Northern Alliance"
• Appoint summarily or commandeer.
  • usage: "The army tried to co-opt peasants into civil defence groups"
• Take or assume for one's own use.
  • usage: "He co-opted the criticism and embraced it"