ei ordbok · dictionary
Feminine (ei)
Indefinite singular
ei ordbok
Definite singular
ordboka
Indefinite plural
ordbøker
Definite plural
ordbøkene
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