Taffeta (archaically spelled taffety or taffata) is a crisp, smooth, plain woven fabric made from silk, cuprammonium rayons, acetate, or polyester. The word came into Middle English via Old French and Old Italian, which borrowed the Persian word tāfta (تافته), which means "silk" or "linen cloth". As clothing, it is used in ball gowns, wedding dresses, and corsets, and in interior decoration for curtains or wallcovering. It tends to yield a stiff, starched-like cloth that holds its shape better than many other fabrics and does not sag or drape.

Silk taffeta is of two types: yarn-dyed and piece-dyed. Piece-dyed taffeta is often used in linings and is quite soft. Yarn-dyed taffeta is much stiffer and is often used in evening dresses. Shot silk taffeta was one of the most highly-sought forms of Byzantine silk, and may have been the fabric known as purpura.