Company and dividend definitions shape taxable income and demerger treatment under the Income-tax Act's foundational terms. Definitions in sections 2(15A)-2(30) supply core terms for the Income-tax Act, 1961: administrative office-holders (Chief Commissioner, Commissioner, Director General/Director and appellate grades); corporate classifications including company, company in which the public are substantially interested, domestic company and foreign company; and tax-substantive concepts-dividend, demerger, income, long-term capital asset/gain and fair market value-together with specified inclusions, exclusions and explanatory qualifications that determine tax treatment.