Wikipedia
Pölsa is a traditional northern Swedish dish, very similar in taste and consistency to Scottish haggis. The main ingredients are liver, heart, onion, pot barley, and often ground beef or minced pork, mixed with stock, black pepper, and marjoram. It is usually served with boiled or fried potatoes, pickled beetroot, and sometimes a fried egg.
The dish plays a central role in Torgny Lindgren's allegorical novel Hash (Pölsan), in which two men go on a personal quest across postwar Sweden in search of the genuine Swedish "pölsa".
The Norwegian and Danish word pølse means sausage and even if the two dishes don't look the same, the two words are related. Pölsa is simply a traditional variety of sausage filling without any casing.
The word pølse can also describe the appearance of an object, like "it looks like a pølse", and "it's pølse shaped" (i.e. sausage shaped).