Muck  —n. 1 colloq. Dirt or filth; anything disgusting. 2 farmyard manure. 3 colloq. Mess. —v. 1 (usu. Foll. By up) colloq. A bungle (a job). B make dirty or untidy. 2 (foll. By out) remove manure from.  make a muck of colloq. Bungle. Muck about (or around) colloq. 1 potter or fool about. 2 (foll. By with) fool or interfere with. Muck in (often foll. By with) colloq. Share tasks etc. Equally. [scandinavian]