Although the noun class system is pretty stable in most of the languages related to Tatediem - Tatediem itself belongs to one of the branches where the system has actually tended to wear down. Tatediem itself is conservative for its branch, keeping a number of classes - some languages that have spread into even closer proximity of Dairwuo-Bryateslean languages, and even more so Ćwarmin-Ŋʒädär-languages, have reduced the noun classes even further.
There are basically seven noun classes, each of which has singular, plural, dual and mass forms. The least "typical" class is the grammatical class, which mainly is used on nouns with various grammatical functions rather than actually denoting referents. Two other classes are familiar from Indo-European and Semitic as well: feminine and masculine.
These contain some non-human, even inanimate nouns. This, mainly, seems to be by loans from more northernly relatives, where the gender system has been further reduced.
The proto language for the highest branch to which Tatediem belongs had something along 34 noun classes - counting singulars, plurals, duals and mass nouns each as separate classes. There isn't clear one-to-one relationships between these classes: some singulars have nouns appear in four to six different plurals, some plurals catch nouns from multiple singular classes, etc. The dual-plural relation seems somewhat stable, though.
A graph illustrating the relationships between Proto-Tatediem noun classes is given below. Numbers 1 to 10 are singular classes, 11 to 15 are plurals, 21 and 22 do not distinguish plurals from duals, 24 and 25 are plurals for which dual marking is impossible (because the nouns tend to appear in large groups and no one would want to single out two out of those groups), 26 is uniquely dual (and marks some pretty specific nouns, and for many of them the plural marker has very peculiar meanings: such as 'my parents' or 'a pair of siblings (inclusive) vs. (exclusive)'. 28 through 34 are mass markers.
Coloured lines are to be interpreted as follows: nouns of class 1 or 2 with 28 as their mass class have 11 (and 16) as their plural (dual) class. The blue line with 2-11-17 are for nouns that are class 11 and 2, but lack class 28 altogether - they have class 17 plurals. 32-14 implies that class 5 nouns with class 14 plurals have class 32 mass marking (or vice versa), and the same goes for 33-22 with regards to 6. The dotted lines that appear here and there are not very common, but have at least a dozen or so nouns. Examples of odd class-jumpers can be found, e.g. náhaŋ, "goose", which goes through classes 29-5-13-20 and also class 32 as goose-meat. However, such oddballs have been largely lost in Tatediem.
1 is primarily masculine, 2 primarily feminine. 28 denotes groups of humans - i.e. tribes, occupations, nationalities, degrees of holiness or status, etc. This may also create abstract nouns such as "kingship" or even "political power".
The bit around 1 and 2 has remained fairly stable in Tatediem, but also creating a complete parallelism between feminine and masculine.
28A - 1 - 11 - 16
28B - 2 - 12 - 17
Classes 3 and 4 (with attendant classes) converged in Tatediem, merging 29, 30 and 31 into a single mass class, and 13 and 14 to a single class - with the same effect in 18 and 19. These are then Neuter 1, singular, dual and mass. Some traces of the different mass classes can be found in retentions of tonal distinctions in the first syllable of certain words, due to the previous class prefix for 29 having had a "migrating" tone, that got expressed on the first syllable after the prefix,, therefore now written dwe.`- in reconstructions. Some class 5 nouns with class 15 plurals migrated to Neuter 1.
Some nouns in Neuter 2 retain class 6's lack of a separate attendant dual class. Other than that, it is mainly the result of 5 and 6 (with attendant classes) collapsing, with just a few class 4 nouns migrating, and about a third of class 7 (with attendant classes).
The remainder of Class 7, as well as classes 8 and 9 (with attendant classes), which previously had a rather large set of vocabulary in them basically very shuffled into two classes, one keeping some class 7 and 8 morphology, the other some class 8 and 9 morphology. The two new classes were likewise "reshaped" to the same singular-dual-plural-mass structure that all other classes had - these are classes 3 and 4.
Finally, the 10, 26, 23 and 27 classes were spread out over the the other classes. Remants of these can be found in formerly class 26 nouns having high tone in the first syllable of their stem in their plural forms even if there's other tones there otherwise.
This leaves the types of nouns prevalent in the different classes rather open-ended:
Neuter 1 has many animals (from classes 3, 4 and 5), some religious festivities, possessions of status, clothing, body parts
Neuter 2 has some animals (from classes 5 and 6), many tools, many plants, spans of time, rocks and minerals, cuts of meat, vessels for seafaring or for travel on land
Neuter 3 has things of geographical extent, abstractions based on geographical concepts, weather-related nouns specific to the drier part of the year, some tools (mainly of wooden type),metals, fruits
Neuter 4 has things of of geographical extent, weather-related nouns specific to the wetter part of the year, many house-related nouns, metallic tools, wooden materials, diseases, containers
Liquids and powders seem spread over all classes' mass number, with individuated bodies of the liquids in the other numbers.
The grammatical class seems to have appeared out of the use of class 10 markers for certain grammatical particles.
The
subclasses of 1 and 2 that are formed with ŋwu- and ku- prefixes seem to be a development that has happened after proto-Tatediem, but the isogloss for it does not cut neatly with any branch division in the larger family, and is thus probably a regional feature.
