The next time you are swirling wine in your glass, notice the way it drips down the inside of the glass. This is called the “legs” or tears of the wine. If the wine is thicker or more full bodied, the liquid runs down the glass more slowly, like paint dripping down a wall. This is called viscosity. If the wine is less viscous, it flows down the side of the glass like water. Seeing the legs is easy. Figuring out what it means is a bit more complicated.
Thirty or more years ago, the legs of the wine were thought to show its quality but this opinion is no longer widely held. Looking at the legs might give you some information about how the wine is going to feel in your mouth, but it won’t tell you much more than that. It isn’t even always accurate regarding the mouth-feel of the wine.
You can learn a lot more from a wine by smelling it and tasting it than you do by ogling its legs.