to mess up, to screw up, to bungle; to coat or cover with mud, to mudden; to stain or dirty with a liquid or pasty, sticky substance; to stain or dirty someone's reputation; to smear or rub with a liquid or pasty, sticky substance
mouth (the end of a river out of which water flows); narrows (narrow part of a river); mouthpiece; embouchure (shape of the mouth and lips when playing a wind instrument); bit (piece of metal placed in a horse’s mouth and connected to the reins)