Plural formation is perhaps one of the trickier aspects of Celinese grammar. To pluralise correctly, one needs to remember if a word is masculine, feminine or neuter; whether or not it has an irregular form, and whether its stem needs to change. For the majority of words, though, it is possible to simply add the plural endings - ím, ot and ain for masculine, feminine and neuter respectively - to an unmodified root. Masculine mythoc (ram) becomes mythocím, feminine gyn (circle) becomes gynot, and neuter alðrír (teacher) becomes alðrírain.
There are, however, some important exceptions:
- words ending in -oê are very common, often used to describe either states or the after-effect of a verb. To bite is tamí; the after-effect of being bitten, a bite, is tamoê, which cannot be pluralised as *tamoêot or tamoot. Instead, the oê becomes oi when pluralised; the standard feminine plural -ot is added after it. Thus, tamoê becomes tamoiot and similarly, noroê (desire) becomes noroiot.
* words including a grave-accented vowel on the last syllable: Grave accents are used to signify that the syllable in which the grave-accented vowel sits carries irregular stress, such as cathàr (martyr), francès (branch - of a business) or awòn (blueberry). These are pronounced [kaˈθaʐ], [fraŋˈgɛs] and [aˈwɔn] - without the breve, all three would be read with the default penult stress (i.e. as [ˈkaθaʐ], [ˈfraŋgɛs] and [ˈawɔn]). When they are pluralised, many speakers omit the breve because stress tends to shift to the penult when plural endings are attached: i.e. to catharain, francesot and awonain, [kaˈθaʐai̯n], [fraŋˈgɛsot] and [aˈwɔnai̯n].
Períseg people and many other northern Elithoan speakers, however, conserve the breve in the plural forms because they do not normally shift to the penult when pluralising. Also, if the grave is on anything but the last syllable, it must remain there. Atèlie (studio) becomes atèliot because the stress is still irregular.
* Words ending in a, e or ë - In these words, feminine by their nature, the vowel is dropped for euphony's sake. Mildë, friend, becomes mildot, not *mildëot. Lauthë becomes lauthot (or its irregular form, leuthain), atèlie becomes atèliot, and ana - you - becomes anot, you all.
Words ending in stressed à, é or è, however, do not clip the vowel; instead an -i- is inserted between the word ending and the plural suffix when the final vowel is à - as in cafà (coffee) becoming cafanot or hosà (cheers) becoming hosanot, whilst with è or í, an -i- is inserted, as in cothlé (steak) becoming cothléiot and bothè (assault) becoming botheiot.
One must also bear in mind a number of irregular plurals. Middle and Late Middle Celinese varieties had hundreds of these, and some dialects (particularly those of the rural parts of West Elitho) retain nearly all of them. However, when the Perís-Ioðinbêr influenced acrolect was standardised, most of the irregular plurals were replaced with ones following a more regular pattern. E.g. mildë (friend) was once pluralised as milðot - [d] to [ð] and [t] to [θ] being a common sound change before plurals. Now, in the standard language, it is the regular 'mildot', but the irregular still remains in many dialects. Some irregular plurals remained (usually because they were irregular in both Perís and Ioðinbêr acrolects). They can generally be divided into three categories:
Nouns whose plural is a different gender to what one would predict from its ending. Two good examples of this would be the word for apple and aspect, eflím [ɛfˈlim] and elym [ˈɛlɪm] respectively. Despite -m being a typically masculine noun ending, the former takes a feminine plural, eflímot, and the latter takes a neuter plural, elymain.
Nouns that are the same in the singular and plural forms - calím (climate), originally the pluralised form of cal, is now used for the singular and plural. The same can be said about dychlain (clothes), which lost its singular form dychıl. Two other key words like this are bairím (fruit/s) and chenosain (evil/s).
Nouns with an irregular plural inflection, such as calbys (hook) turning to ca(u)lsain in the plural, hidim (insect) to hiðmain, aðel (Elithoan currency) to aðail, selmoth (second) to selmaith and talom (space) to taloim.