20 C.F.R. § 416.702
For purposes of this subpart-
Essential person means someone whose presence was believed to be necessary for your welfare under the State program that preceded the SSI program. (See §§ 416.220 through 416.223 of this part.)
Parent means a natural parent, an adoptive parent, or the spouse of a natural or adoptive parent.
Representative payee means an individual, an agency, or an institution selected by us to receive and manage SSI benefits on your behalf. (See subpart F of this part for details describing when a representative payee is selected and a representative payee's responsibilities.)
Residence in the United States means that your permanent home is in the United States.
United States or U.S. means the 50 States, the District of Columbia, and the Northern Mariana Islands.
We, Us, or Our means the Social Security Administration.
You or Your means an applicant, an eligible individual, an eligible spouse, or an eligible child.
20 C.F.R. §416.702