In this chapter - (1) the definitions in section 502 of the National Aeronautics and Space Administration Authorization Act, Fiscal Year 1993 (15 U.S.C. 5802) apply. (2) "commercial space transportation infrastructure development" includes - (A) construction, improvement, design, and engineering of space transportation infrastructure in the United States; and (B) technical studies to define how new or enhanced space transportation infrastructure can best meet the needs of the United States commercial space transportation industry. (3) "project" means a project (or separate projects submitted together) to carry out commercial space transportation infrastructure development, including the combined submission of all projects to be undertaken at a particular site in a fiscal year. (4) "project grant" means a grant of an amount by the Secretary of Transportation to a sponsor for one or more projects. (5) "public agency" means a State or an agency of a State, a political subdivision of a State, or a tax-supported organization. (6) "sponsor" means a public agency that, individually or jointly with one or more other public agencies, submits to the Secretary under this chapter an application for a project grant.