"Yeasty" is a tasting term that describes wine that has the aroma or taste of yeast (similar to the smell of fresh-baked bread). It's an expected and desirable trait in Champagne that has spent three or more years on the lees, which allows it to develop a yeasty aroma or character (see secondary fermentation). If a young table wine smells overly yeasty, however, it usually indicates that the wine needs to be aged longer to allow the residual yeast to dissipate.