- The nominative singular ends in -i, the other singular cases end in -a or -ja.
- The noun is derived from the present participle of a verb, in which case the plural ends in -ur (but the singular follows the -i-a rule).
An example of the latter is nemandi (student), plural nemendur. The words bóndi (farmer) and fjandi (enemy or the devil or a demon) belong to this class with some irregularities. The plural of bóndi is bændur. Fjandi has two plurals, depending on the meaning. If it means an enemy, the plural is fjendur (note the retention of je). If it means a demon, the plural is fjandar.
Exceptions do exist, for instance Grikki (Greek), plural Grikkir. The same applies to Tyrki (Turk) plural Tyrkir. Both, incidentally, end in -ja in the oblique cases (Grikkja is the accusative, dative and genitive for one Greek).
- The nominative singular ends in -a, the other singular cases end in -u.
- The singular ends in -i in all cases. (If there is a plural, it may end in either -ir or -ar.)
- They end in -a in the singular in all cases. The plural ends in -u (but the genitive plural in -na) without further alterations with the exception of hjarta (heart) which becomes hjörtu in the plural through u-umlaut. The genitive plural, however is hjartna showing a-breaking instead of u-breaking. Some borrowings may exhibit similar behaviour, e.g, singular drama, plural drömu. Most of these are words for organs.
An almost exhaustive list follows:
- auga (eye)
- bjúga (a type of sausage)
- eista (testicle)
- eyra (ear)
- hjarta (heart)
- hnoða (a woollen ball, most often encountered in fairy-tales)
- lunga (lung)
- milta (spleen)
- nýra (kidney)
Then there are a small number of borrowings like firma, drama, þema etc. none of which require translation.
- Björn Guðfinnsson (1958). Íslensk málfræði Námsgagnastofnun.