Lank describes hair that hangs straight down in a limp, lifeless way, without any bounce or body. When someone's hair is lank, it lies flat against their head like wet spaghetti, looking thin and often a bit greasy or unwashed. You might notice your own hair getting lank on a hot summer day after running around outside, or after several days without washing it.

That thinness is part of what makes lank hair look so droopy. While straight hair can look sleek and healthy, lank hair looks tired and neglected.

Less commonly, lank can describe anything that's tall, thin, and drooping: a lank plant that needs watering, or even a very thin person with poor posture. But you'll most often encounter it describing hair that's lost its life and volume.