Entry 1 sense Webster, 1913 Furlong /fẽrl'-ôngˌ/ · Fur·long · IPA /ˈfɝˌlɔŋ/ 01 n. A measure of length; the eighth part of a mile; forty rods; two hundred and twenty yards. 1. A measure of length; the eighth part of a mile; forty rods; two hundred and twenty yards.