From Longman Business Dictionarybook-to-bill ratioˌbook-to-ˈbill ˌratio American EnglishACCOUNTING an amount showing the number of new orders received by a company compared to the number of products sold by the companyIts book-to-bill ratio rose to 1.08, which means that for every $100 of microchip orders that are shipped, manufacturers received $108 of new orders. → ratio