Pennate is used to mean "winged", "feathered" or simply "shaped like a wing". The latter definition is sometimes used to describe plant leaf morphology (see lanceolate).
Pennate diatoms are bilaterally symmetrical, and belong to the order Pennales.
Pennate muscles are fascicle that are attached to tendons. The terms unipennate and bipennate are used anatomically in reference to feather-shaped muscles, such as extensor digitorum longus.