From Longman Business DictionaryStandard & Poor’s IndexˌStandard & ˈPoor’s ˌIndex (also Standard & Poor’s 500 stock index), abbreviation S&P 500 [singular]FINANCE a measure of changes on the stockmarket, based on the performance of shares in 500 large US companiesThe Standard & Poor’s index of 500 stocks was down 0.17 point to 396.47. → index
