Nephrolepis exaltata, the sword fern, is a species of fern in the family Lomariopsidaceae (sometimes treated in the families Davalliaceae or Oleandraceae, or in its own family, Nephrolepidaceae), native to tropical regions throughout the world.

It is common in humid forests and swamps, especially in northern South America, Mexico, Central America, Florida, the West Indies, Polynesia and Africa. Also known as the Boston swordfern, wild Boston fern, tuber ladder fern, or fishbone fern — it is in the broader family of sword fern.