1)    gen sg-s, nom pl-ar

Like jökull: all bisyllabic masculines ending in -ll in nom (gen -ls).

Like læknir: all masculines ending in -ir in nom (pl -ar).

2)    gen sg-s/-jar, nom pl-ir

3)    gen sg-ar, nom pl-ir

Nouns ending in -aður have the vowel change like fagnaður (-a- > -u- in the dat pl, while those ending in -uður follow the pattern of söfnuður.

4)    Special cases:

5)    gen sg-a, nom pl-ar

6)    gen sg-a, nom pl-ur; gen sg-a, nom pl-ir

Like byrjandi; all weak masculines ending in -andi. Dani and bóndi are special cases.

7)    gen sg and nom pl-ar/-jar/ -var/-r

Feminine nouns ending in -i which take -ar in the gen sg are declined as ermi while those ending in -ing/-ung and proper names are declined like kerling.

8)    gen sg-ar, nom pl-ir

All nouns with the suffix -un are declined like verslun.

9)    gen sg-ar, nom pl-ur/-r

10)    gen sg-ur/-r/-ar, nom pl-ur/-r/-

móðir has no vowel change in the sg forms, while in the pl the vowel change is universal. dóttir and systir follow the same pattern but the latter has no change in the vowel; like mús is lús.

11)    gen sg-u, nom pl-ur

The presence or absence of -n- in the gen pl is partly independent of the stem.

12)    gen sg-i, nom pl-ar/-ir.

13)    gen sg-s, nom pl-

14)    gen sg-a, nom pl-u