For the purposes of this chapter, except as may be specifically provided otherwise, the term—
(1) “child custody proceeding” shall mean and include—
“foster care placement” which shall mean any action removing an Indian child from its parent or Indian custodian for temporary placement in a foster home or institution or the home of a guardian or conservator where the parent or Indian custodian cannot have the child returned upon demand, but where parental rights have not been terminated;
“extended family member” shall be as defined by the law or custom of the Indian child’s tribe or, in the absence of such law or custom, shall be a person who has reached the age of eighteen and who is the Indian child’s grandparent, aunt or uncle, brother or sister, brother-in-law or sister-in-law, niece or nephew, first or second cousin, or stepparent;
“Indian child’s tribe” means (a) the Indian tribe in which an Indian child is a member or eligible for membership or (b), in the case of an Indian child who is a member of or eligible for membership in more than one tribe, the Indian tribe with which the Indian child has the more significant contacts;
“reservation” means Indian country as defined in section 1151 of title 18 and any lands, not covered under such section, title to which is either held by the United States in trust for the benefit of any Indian tribe or individual or held by any Indian tribe or individual subject to a restriction by the United States against alienation;
“tribal court” means a court with jurisdiction over child custody proceedings and which is either a Court of Indian Offenses, a court established and operated under the code or custom of an Indian tribe, or any other administrative body of a tribe which is vested with authority over child custody proceedings.