Samara: A dry, indehiscent, winged fruit.*
Tulip trees (Liriodendron tulipifera), maples (Acer spp.), and many other plants produce samaras, commonly referred to as ‘keys.’ Tulip trees, pictured above, often have whorls of samaras persisting through the winter, giving the impression of flowers.
*Harris, J.G., Harris, M.W. (2001). Plant identification terminology: An illustrated glossary (2nd ed.). Spring Lake: Spring Lake Publishing.