crud I. \ˈkrəd, ˈkru̇d\noun (-s) Etymology: Middle English crudd — more at curd 1.dialect: curd I 2.: a deposit or incrustation of filth, grease, or refuse : an impurity or unwanted foreign substance 3.: a usually ill-defined or imperfectly identified bodily disorder < jungle crud > • crud·dy\-dē\adjective II. verb (crudded ; crudded ; crudding ; cruds) Etymology: Middle English crudden — more at curd dialect: curd II