ˈkɹuːsɪfaɪ fɹəˈstɹeɪt ˈfɹʌstɹeɪt make a dun color of a dull greyish brown to brownish grey color the dun and dreary prairie cure by salting dun codfish persistently ask for overdue payment The grocer dunned his customers every day by telephone treat cruelly The children tormented the stuttering teacher horse of a dull brownish grey color a color or pigment varying around a light grey-brown color she wore dun