Oilcloth is a tightly woven cotton or linen cloth which has been treated on one side to make it waterproof.  Originally it had a linseed oil coating, but nowadays it is usually PVC coated.  Don’t get mixed up between Oilcloth and the cheaper PVC.  Oilcloth has the design printed onto the cotton before a protective PVC layer is applied, whereas PVC is a vinyl which has been surface printed.