Any fabric having a thick soft shag, like the fur of a mole; esp., a kind of strong twilled fustian. [1913 Webster]
A soft fabric having an adhesive backing, applied to the skin at points susceptible to abrasion, as on the feet, to prevent irritation or blistering during exercise, such as hiking. [PJC]
moleskin, n.
1 the skin of a mole used as fur.
2 a a kind of cotton fustian with its surface shaved before dyeing. b (in pl.) clothes, esp. trousers, made of this.