From Longman Dictionary of Contemporary Englishpro ratapro ra‧ta /prəʊ ˈrɑːtə $ proʊ ˈreɪtə/ adjective [only before noun] especially British English BFa payment or share that is pro rata is calculated according to how much of something is used, how much work is done etc Fees are calculated on a pro rata basis. —pro rata adverbFrom Longman Business Dictionarypro ratapro ra‧ta /prəʊ ˈrɑːtəproʊ ˈreɪtə/ adjective [only before a noun] a pro rata payment or share in something is calculated according to exactly how much of something is used, how much work is done etcThe residents here pay more than their pro rata share of taxes.Fees for longer or shorter courses are calculated on a pro rata basis. —pro rata adverbThe company directors are required to allot the shares to existing shareholders pro rata to the number of shares owned.Origin pro rata (1500-1600) Latin “for the rate”
