In this Act, unless the context otherwise requires:

(xxv) "taxable turnover" means the turnover on which a dealer shall be liable to pay tax as determined after making such deductions from his total turnover and in such manner as may be prescribed, but shall not include the turnover of purchases or sale in the course of interstate trade or commerce or in the course of export of the goods out of the territory of India or in the course of import of the goods into the territory of India;