ei pølse · sausage
Feminine (ei)
Indefinite singular
ei pølse
Definite singular
pølsa
Indefinite plural
pølser
Definite plural
pølsene
Feminine nouns (ei) can always be written with en as well: ei bok, boka or en bok, boken. Both are correct Bokmål.
How to guess the gender Nouns: gender and articles