To take by choice into relationship, as, child, heir, friend, citizen, etc.; esp. to take voluntarily (a child of other parents) to be in the place of, or as, one's own child.

To take or receive as one's own what is not so naturally; to select and take or approve; as, to adopt the view or policy of another; these resolutions were adopted.

To take and apply or put into action.

A court procedure in which an adult becomes the legal parent of someone who is not his or her biological child.

To take legal responsibility and assume the role of parent to someone else's child.

is to legally join one or more parents and a child not born to them into a family.

take up and practice as one's own

take on titles, offices, duties, responsibilities; "When will the new President assume office?"

take on a certain form, attribute, or aspect; "His voice took on a sad tone"; "The story took a new turn"; "he adopted an air of superiority"; "She assumed strange manners"; "The gods assume human or animal form in these fables"

take into one's family; "They adopted two children from Nicaragua"

take up the cause, ideology, practice, method, of someone and use it as one's own; "She embraced Catholicism"; "They adopted the Jewish faith"

To become a child's parent without being his natural parent. Also to approve or accept something.

Adopted Child

(1) To assume the legal relationship of parent to another person's child. See also adoption. (2) To approve or accept something -- for example, a legislative body may adopt a law or an amendment, a government agency may adopt a regulation or a party to a lawsuit may adopt a particular argument.