To appoint summarily (with or without the appointee's consent).
To appropriate (something rightly belonging to another) as one's own; to preempt; as, to co-opt someone's name.
neutralize or win over through assimilation into an established group; "We co-opted the independent minority tribes by pulling them into the Northern Alliance"
appoint summarily or commandeer; "The army tried to co-opt peasants into civil defence groups"
take or assume for one's own use; "He co-opted the criticism and embraced it"