General definitions govern DTAA terms: person, company, enterprise, national and competent authority for tax treaty application. The Convention supplies core definitions for treaty application including territorial scope for India and the Kingdom of Saudi Arabia, and defines person, company, enterprise, and international traffic. It designates each State's competent authority and the meaning of national for individuals and legal persons. Terms not defined in the Convention take their contemporaneous meanings under the domestic tax law of the relevant Contracting State, with tax-law meanings prevailing over other domestic-law meanings.