Taenioid is a scientific term that describes a body shape that is long, narrow and ribbon-like. Some synonyms for taenioid include ribbon-like, worm-like and elongated. Other related terms to taenioid include serpentine or serpentiform, which describes an elongated shape similar to that of a snake or serpent. Other synonyms for taenioid include filiform, which describes a thread-like shape, and vermiform, which describes a shape resembling a worm. The term taenioid is often used in biology to describe certain fish species that have an elongated and ribbon-like body shape, such as the needlefish or garfish.