That can be referred to as tough or compared to cotton.
Tannin, astringency or texture: Found primarily in reds, tannin comes from the skin, seeds and stems of grapes. In the mouth, tannin might feel like sucking on a cotton napkin, like all the moisture has left your mouth, like your tongue is suddenly furry. Tannin is one of the factors that contributes to texture. Similar to body, texture has a lot to do with how the wine feels. Is it suddenly hard to move your tongue against the roof of your mouth? That can be referred to as tough or compared to cotton. Or does your tongue feel slippery? That's called silky or soft.