All Zulu nouns belong to a particular class, a little bit like French nouns having a gender. However, there are 17 different classes, six of which are plural forms. The different noun classes are created through the following class prefixes:

umu-/um- and corresponding plural aba-
u- and corresponding plural o-
umu- and corresponding plural imi-
ili-/i- and corresponding plural ama-
isi- and corresponding plural izi-
in- and corresponding plural izin-
ulu-/u-
ubu-
uku-
pha-
ku-

The remaining part of the noun is called the noun stem and remains constant. It is modern practice to list nouns alphabetically according to the noun stem rather than the class prefix. Notice that in some cases, such as with in- (plural: izin-) the final consonant may be considered part of both the prefix and the stem.