Arnel is the trademark name of a synthetic fiber developed in the 1950s. It was popular at first, but production was discontinued by the manufacturer in 1986 due to concerns about the toxicity of a chemical used to manufacture the fiber.

Arnel is the name of cellulose triacetate made from processing tree fibers. It is considered an offshoot of nylon, like the more commonly known rayon. It is often blended with polyester.

Arnel threads are woven together or blended with other fabric threads to create cloth. Primarily used in clothing, Arnel can also be used in other home goods such as rugs and blankets.

By itself, Arnel is a crisp fabric with a smooth, dull finish. It is often used in a woven material called "sharkskin" that is also known for being smooth and crisp. Arnel clothing is machine washable. It retains its whiteness, unlike other synthetic fabrics that can yellow over time.