38 C.F.R. § 21.5720
For the purpose of regulations in the §§ 21.5700, 21.5800 and 21.5900 series and payment of benefits under the educational assistance and subsistence allowance program, the following definitions apply:
(a) Veteran. This term means a person who—
(4) Meets the eligibility requirements for the program as stated in § 21.5740.
(Authority: 10 U.S.C. 2141(a))
(b) Accredited institution. This term means a civilian college or university or a trade, technical or vocational school in the United States (including the District of Columbia, the Commonwealth of Puerto Rico, Guam and the U.S. Virgin Islands) that—
(2) Is accredited by—
(ii) An accrediting agency or association recognized by the Secretary of Education.
(Authority: 10 U.S.C. 2143(c))
(c) Dependent child. This means an unmarried legitimate child (including an adopted child or a stepchild) who either—
(3) Has not passed his or her 23rd birthday; is enrolled in a full-time course of study in an institution of higher learning approved by the Secretary of Defense or the Secretary of Education, as the case may be; and is, or was at the time of the veteran's or servicemember's death, in fact, dependent upon him or her for over one half of his or her support.
(Authority: 10 U.S.C. 1072(2)(D), 2147(d)(1))
(d) Surviving spouse. The term means a widow or widower who is not remarried.
(Authority: 10 U.S.C. 2147(d)(2))
(e) Servicemember. This term means anyone who—
(2) Is on active duty in the Air Force, Army, Navy or Marine Corps.
(Authority: 10 U.S.C. 2142)
(f) Spouse. This term means a person of the opposite sex who is the husband or wife of the veteran or servicemember.
(Authority: 10 U.S.C. 2147)
(g) Divisions of the school year.
(4) Term is either
(ii) The period of instruction which takes place between standard academic years.
(Authority: 10 U.S.C. 2142)
(h) Full-time training. This term means training at the rate of 12 or more semester hours per semester, or the equivalent.
(Authority: 10 U.S.C. 2144)
(i) Part-time training. The term means training at the rate of less than 12 semester hours per semester or the equivalent.
(Authority: 10 U.S.C. 2144)
(j) Enrollment period. This term means an interval of time during which an eligible individual—
(2) Is pursuing his or her program of education.
(Authority: 10 U.S.C. 2142)