42 USC 113434A - General Definition of Homeless Children and Youth
For purposes of this part:
(i) children and youths who are sharing the housing of other persons due to loss of housing, economic hardship, or a similar reason; are living in motels, hotels, trailer parks, or camping grounds due to the lack of alternative adequate accommodations; are living in emergency or transitional shelters; are abandoned in hospitals; or are awaiting foster care placement;
(ii) children and youths who have a primary nighttime residence that is a public or private place not designed for or ordinarily used as a regular sleeping accommodation for human beings (within the meaning of section 11302 (a)(2)(C) of this title);
(iv) migratory children (as such term is defined in section 6399 of title 20) who qualify as homeless for the purposes of this part because the children are living in circumstances described in clauses (i) through (iii).