adopt (someone or something) as (something)
1. To choose one for a specific role. We were so impressed with her efforts that we adopted her as the new leader of the organization.
2. To claim ownership of something or establish guardianship or someone. I told Marshall my idea for the project last week, and now he has apparently adopted it as his own. My parents adopted me as their son when I was just two months old.
adopt someone as something
to choose someone as something. The committee will adopt Jane as its candidate.
adopt something as something
to take on something, such as a policy or principle, as one's own. I will adopt this policy as my own.