Okla. Stat. tit. 10, § 10-40.2
Definitions
For the purposes of the Oklahoma Indian Child Welfare Act:
1. "Indian" means a person who is a member of an Indian tribe;2. "India
a.
a member of an Indian tribe, or
b.
is eligible for membership in an Indian tribe and is
the biological child of a member of an Indian tribe;
3. "Indian custodian" means any Indian person who has legal
custody of an Indian child under tribal law or custom or under state
law or to whom temporary physical care, custody and control has been
transferred by the parent of such child; and
4. "Indian tribe" means any Indian tribe, band, nation or other
organized group or community of Indians recognized as eligible for
the services provided to Indians by the Secretary of the Interior
because of their status as Indians.