fern - any of numerous flowerless and seedless vascular plants having true roots from a rhizome and fronds that uncurl upward; reproduce by spores

genus Nephrolepis, Nephrolepis - small genus of tropical ferns; sometimes placed in Polypodiaceae

Boston fern, Nephrolepis exaltata, Nephrolepis exaltata bostoniensis - a sword fern with arching or drooping pinnate fronds; a popular houseplant

basket fern, Nephrolepis pectinata, toothed sword fern - tropical American fern cultivated for its finely divided grayish-green foliage; West Indies and southern Mexico to Peru and Brazil