A knish is an eastern-European Jewish or Yiddish snack food. It is a dumpling covered with a dough shell that is either baked or fried. In the most traditional version, the dumpling is made entirely of mashed potato. Another version has the dumpling made of a combination of mashed potato and ground beef.

It is similar to the slavic pierogi, the Spanish and Latin American empanada, and the South Asian samosa.

Unlike normal dumplings, which tend to be round in shape, knishes are flatter. The commercial versions are similiar in shape to frozen fried fish filet patties. The eastern-European versions are hors d'oeuvre sized while the New York City versions are the size of hamburgers.