canvas

A heavy, strong, usually plain weave fabric that historically was made of flax, hemp, or cotton. Today, it is usually made of cotton, but some fabrics made of man-made fibers or blends are also called canvas. Canvas is, roughly speaking, heavier than duck or sailcloth although the three names are often used interchangeably. The unbleached fabric is used for coat fronts, lapels, and linings of men’s suits. Hair canvas for interlinings is made of goat’s hair and wool. See duck and sailcloth.