NOUN CLASSES

In common with all Bantu languages, Swahili grammar arranges nouns into a number of classes. The ancestral system had 22 classes, counting singular and plural as distinct according to the Meinhof system, with all Bantu languages sharing at least ten of these. Swahili employs fourteen: six classes singular and plural, a class for verbal infinitives used as nouns, and the single noun mahali "place".

Nouns beginning with m- in the singular and wa- in the plural denote animate beings, especially people. Examples are mtu, meaning 'person' (plural watu), and mdudu, meaning 'insect' (plural wadudu). A class with m- in the singular but mi- in the plural often denotes plants, such as mti 'tree', miti trees. The infinitive of verbs begins with ku-, e.g. kusoma 'to read'. Other classes are harder to categorize. Singulars beginning in ki- take plurals in vi-; they often refer to hand tools and other artifacts. This ki-/vi- alteration even applies to foreign words where the ki- was originally part of the root, so vitabu "books" from kitabu "book" (from Arabic kitāb "book"). This class also contains languages (such as the name of the language Kiswahili), and diminutives, which had been a separate class in earlier stages of Bantu. Words beginning with u- are often abstract, with no plural, e.g. utoto 'childhood'.

A fifth class begins with n- or m- or nothing, and its plural is the same. Another class has ji- or no prefix in the singular, and takes ma- in the plural; this class is often used for augmentatives. When the noun itself does not make clear which class it belongs to, its concords do. Adjectives and numerals commonly take the noun prefixes, and verbs take a different set of prefixes.

singular				plural
mtoto	mmoja	anasoma		watoto	wawili	wanasoma
child	one	is reading		children	two	are reading
One child is reading				Two children are reading
kitabu	kimoja	kinatosha		vitabu	viwili	vinatosha
book	one	suffices		books	two	suffice
One book is enough				Two books are enough
ndizi	moja	inatosha		ndizi	mbili	zinatosha
banana	one	suffices		bananas	two	suffice
One banana is enough				Two bananas are enough

The same noun root can be used with different noun-class prefixes for derived meanings: human mtoto (watoto) "child (children)", abstract utoto "childhood", diminutive kitoto (vitoto) "infant(s)", augmentative toto (matoto) "big child (children)". Also vegetative mti (miti) "tree(s)", artifact kiti (viti) "stool(s)", augmentative jiti (majiti) "large tree", kijiti (vijiti) "stick(s)", ujiti (njiti) "tall slender tree".

Although the Swahili noun class system is technically grammatical gender, there is a difference from the grammatical gender of European languages: In Swahili, the class assignments of nouns is still largely semantically motivated, whereas the European systems are mostly arbitrary. However, the classes cannot be understood as simplistic categories such as 'people' or 'trees'. Rather, there are extensions of meaning, words similar to those extensions, and then extensions again from these. The end result is a semantic net that made sense at the time, and often still does make sense, but which can be confusing to a non-speaker.

Take the ki-/vi- class. Originally it was two separate genders: artifacts (Bantu class 7/8, utensils & hand tools mostly) and diminutives (Bantu class 12). Examples of the first are kisu "knife"; kiti "chair, stool", from mti "tree, wood"; chombo "vessel" (a contraction of ki-ombo). Examples of the latter are kitoto "infant", from mtoto "child"; kitawi "frond", from tawi "branch"; and chumba (ki-umba) "room", from nyumba "house". It is the diminutive sense that has been furthest extended. An extension common to many languages is approximation and resemblance (having a 'little bit' of some characteristic, like -y or -ish is English). For example, there is kijani "green", from jani "leaf" (compare English 'leafy'), kichaka "bush" from chaka "clump", and kivuli "shadow" from uvuli "shade". A 'little bit' of a verb would be an instance of an action, and such instantiations (usually not very active ones) are also found: kifo "death", from the verb -fa "to die"; kiota "nest" from -ota "to brood"; chakula "food" from kula "to eat"; kivuko "a ford, a pass" from -vuka "to cross"; and kilimia "the Pleiades, from -limia "to farm with", from its role in guiding planting. A resemblance, or being a bit like something, implies marginal status in a category, so things that are marginal examples of their class may take the ki-/vi- prefixes. One example is chura (ki-ura) "frog", which is only half terrestrial and therefore marginal as an animal. This extension may account for disabilities as well: kilema "a cripple", kipofu "a blind person", kiziwi "a deaf person". Finally, diminutives often denote contempt, and contempt is sometimes expressed against things that are dangerous. This might be the historical explanation for kifaru "rhinoceros", kingugwa "spotted hyena", and kiboko "hippopotamus" (perhaps originally meaning "stubby legs").

Another class with broad semantic extension is the m-/mi- class (Bantu classes 3/4). This is often called the 'tree' class, because mti, miti "tree(s)" is the prototypical example, but that doesn't do it justice. Rather, it seems to cover vital entities which are neither human nor typical animals: trees and other plants, such as mwitu 'forest' and mtama 'millet' (and from there, things made from plants, like mkeka 'mat'); supernatural and natural forces, such as mwezi 'moon', mlima 'mountain', mto 'river'; active things, such as moto 'fire', including active body parts (moyo 'heart', mkono 'hand, arm'); and human groups, which are vital but not themselves human, such as mji 'village', perhaps msikiti 'mosque', and, by analogy, mzinga 'beehive'. From the central idea of tree, which is thin, tall, and spreading, comes an extension to other long or extended things or parts of things, such as mwavuli 'umbrella', moshi 'smoke', msumari 'nail'; and from activity there even come active instantiations of verbs, such as mfuo "hammering", from -fua "to hammer", or mlio "a sound", from -lia "to make a sound". Words may be connected to their class by more than one metaphor. For example, mkono is an active body part, and mto is an active natural force, but they are also both long and thin. Things with a trajectory, such as mpaka 'border' and mwendo 'journey', are classified with long thin things in many languages. This may be further extended to anything dealing with time, such as mwaka 'year' and perhaps mshahara 'wages'. Also, animals which are exceptional in some way and therefore don't fit easily in the other classes may be placed in this class.

The other classes have foundations that may at first seem similarly counterintuitive