(a) Secretary means the Secretary of the Interior or his authorized representative acting under delegated authority.

(b) Agency means an Indian agency or other field unit of the Bureau of Indian Affairs having trust or restricted Indian land under its immediate jurisdiction.

(c) Restricted land means land or any interest therein, the title to which is held by an individual Indian, subject to Federal restrictions against alienation or encumbrance.

(d) Trust land means land or any interest therein held in trust by the United States for an individual Indian.

(e) Competent means the possession of sufficient ability, knowledge, experience, and judgment to enable an individual to manage his business affairs, including the administration, use, investment, and disposition of any property turned over to him and the income or proceeds therefrom, with such reasonable degree of prudence and wisdom as will be apt to prevent him from losing such property or the benefits thereof. (Act of August 11, 1955 (69 Stat. 666)).

(f) Tribe means a tribe, band, nation, community, group, or pueblo of Indians.