binder Syllabification: (bind·er)Pronunciation: /ˈbīndər/Translate binder | into French | into German | into Italian | into Spanish Definition of binder noun a thing or person that binds something, in particular. a cover for holding loose sheets of paper, magazines, etc., together. a substance that acts cohesively. a reaping machine that binds grain into sheaves. a bookbinder. binder in other Oxford dictionaries Definition of binder in the British & World English dictionary