de·fi·brate \(ˈ)dēˈfīˌbrāt\transitive verb (-ed/-ing/-s) Etymology:de- + Latin fibra fiber + English -ate — more at fiber : to separate (as a pulp sheet, waste paper, partly cooked wood) into its fibrous constituents • de·fi·bra·tion\ˌdēˌfīˈbrāshən\noun-s