Classical Arithide declension
Owing to the language's inflectionary nature, Classical Arithide nouns, pronouns and certain of its adjectives must be declined (i.e. inflected) to provide grammatical meaning. A group of words that decline in the same way is known as a "declension class". There are 8 declension classes for nouns and the same for adjectives; pronouns are generally irregular.
Declension classes
Nouns in Classical Arithide are classed into different declensions based on their semantic meaning. This lexically based categorisation means that each declension class represents a broad group of nouns that share a certain characteristic. Traditional grammatical analysis takes the number of declension classes in Classical Arithide to be six, but the sub-classes that are sometimes sufficiently distinct from their ostensible parent class render the number about double. Factoring in overlapping and coincident declensions, modern grammarians generally accept the existence of 8 discrete groups, numbered declension classes I to VIII respectively. Only 7 classes were lexical: classes I to IV were productive classes due to their nature—they are still productive in Modern Arithide—and the separate but largely coincident declensions of the nouns thence derived were categorised under an eighth class.
Nouns of the first declension end in -os, and are associated lexically with abstractions: actions (vagos, "act of going"), states (stantos, "weight"), qualities (fugirnos, "dangerousness"), among others (sonos, "daily life"). The second declension ends in -as and is associated with places: kitaras "hall". The third (-ir) and fourth (-rir) both indicate a negative denotation or connotation associated with the noun, and were treated traditionally as variants of one declension, but separately nowadays because of the differences in their declension; they are also the only declensions where disyllabic nouns are stressed on the last syllable; vokir "evil", kirir "faux pas". The fifth declension consists of nouns ending in either -er or -a, and the association here is with people, society and culture: ither "person", medier "wife", steima "measurement". The sixth declension consists solely of the agentive derivatives of verbs, and hence all end in -on, e.g. forion "miner". The seventh is made up of nouns ending in -i, but no apparent lexical connection has been found that sufficiently encompasses the nouns in the category. The eighth, and last, declension class comprises the derived nouns, ending in any of -os, -as or -ir, and is the most regular declension class due to its character: it is the only class in which no irregularity is observed in any individual noun.
Grammatical cases
Fully declining a noun requires expressing its 11 cases:
- Nominative, which marks the subject of a verb; the nominative is the case in which a noun or pronoun is cited in the dictionary, hence it is also known as the citation case
- Topical, which marks the topic of a sentence
- Accusative, which marks the object of a verb
- Genitive, which marks possession by
- Dative, which marks motion towards, and by extension benefaction to etc.
- Locative, which marks location (with places) or indicates shift of grammatical focus (with objects and people)
- Ablative, which marks motion away or existence apart, and by extension is used with prepositions such as parō "about, regarding" or etel "by (agentive)"
- Instrumental, which marks instruments, and by extension accompaniment, using the preposition etel "with"
- Vocative, which marks direct address
- Connective, which is an open-ended stem form to which certain affixes or other nouns are appended, e.g. salumos "heaven" + innos "top" > saluminnum "in heaven" (lit. "on heaven"; innos is in the locative) and allas "city" + dolō "around" (from dolos "surroundings") > alladolō "around the city" 1
- Essive, which marks existence as
1
Alladolō (connective + prep.) must be distinguished from the similar dolō allior (prep. + ablative); while both might be translated as "around the city", the former refers to the areas outside and surrounding a certain city, while the latter refers to places all around within the city: alladolō siethē sena "there are flowers around the city" vs. dolō allior siethē sena "there are flowers all about the city".
Of these, the connective and essive cases in all nouns are identical, resulting in 10 effective cases.
First declension -os
Nouns of and adjectives in the first declension take the following endings:
| CASE | sg. | pl. |
| NOM | -os | -ēs |
| TOP | -ou | -ōi |
| ACC | -o | -ē |
| GEN | -en, -ne1 | -enē(s)2 |
| DAT | -ae | -ei |
| LOC | -ira | -erē |
| ABL | -ōn | -ēn |
| INS | -itis | -itēs |
| VOC | -ō | -ē |
| CON/ESS | - | -er, -er- |
1 The former -en is used with consonant-stem words (e.g. sōmos, sōm-), while the latter with vowel-stem words (e.g. thiftios, thifti-).
2 The final -s is optional, but tends to be used in more formal speech, and all writing (except in imitations of speech or transcriptions).
Sample declensions with the nouns sōmos and thiftios are given below:
| CASE | sg. | pl. | sg. | pl. |
| NOM | sōmos | sōmēs | thiftios | thiftiēs |
| TOP | sōmou | sōmōi | thiftiou | thiftiōi |
| ACC | sōmo | sōmē | thiftio | thiftiē |
| GEN | sōmen | sōmenē(s) | thiftine | thiftinē(s) |
| DAT | sōmae | sōmei | thiftiae | thiftiei |
| LOC | sōmira | sōmerē | thiftira | thiftirē |
| ABL | sōmōn | sōmēn | thiftiōn | thiftiēn |
| INS | sōmitis | sōmitēs | thiftitis | thiftitēs |
| VOC | sōmō | sōmē | thiftiō | thiftiē |
| CON/ESS | sōm- | sōmer, sōmer- | thifti- | thiftier, thiftier- |
Second declension -as
Second declension nouns take the following endings:
| CASE | sg. | pl. |
| NOM | -as | -ae |
| TOP | -ai | -ēi |
| ACC | -a | -ē |
| GEN | -an | -anē(s)1 |
| DAT | -is2 | -ēs |
| LOC | -um | -ām |
| ABL | -ior3 | -ēri |
| INS | -atis | -etēs |
| VOC | -ā | -ē |
| CON/ESS | -a, -a- | -ē, -ē- |
1 The final -s is optional, but tends to be used in more formal speech, and all writing (except in imitations of speech or transcriptions).
2 With -i- stem words, the coagulation of the -i- in the noun stem and that in the ending gives rise to a resultant long ī.
3 In this case the -i- in the case ending is elided.
Unlike the first declension, nouns of the second declension do not distinguish endings between consonant- and vowel-stem words. An example conjugation is provided with sivias "town" below.
| CASE | sg. | pl. |
| NOM | sivias | siviae |
| TOP | siviai | siviēi |
| ACC | sivia | siviē |
| GEN | sivian | sivianē(s) |
| DAT | sivīs1 | siviēs |
| LOC | sivium | siviām |
| ABL | sivior2 | siviēri |
| INS | siviatis | sivietēs |
| VOC | siviā | siviē |
| CON/ESS | sivia, sivia- | siviē, siviē- |
1 The long ī derives from the coagulation of the -i- in the noun stem and that in the ending.
2 In this case the -i- in the case ending is elided.
Third declension -ir
The important distinction between nouns that end in the simpler -ir and more complex -rir endings (declensions III and IV respectively) must be maintained for purposes of proper declension. Third declension nouns form their stems differently (in many cases with the retention of the -ir ending), and take endings that vary markedly from those of the fourth declension.
The endings for the third declension are:
| CASE | sg. | pl. |
| NOM | -ir | -idēs |
| TOP | -u, -irou1 | -idōi |
| ACC | -i, -u1 | -idē |
| GEN | -uris | -idis |
| DAT | -irae | -idei |
| LOC | -irum | -idēm |
| ABL | -irōn | -idēn |
| INS | -iritis | -iditēs |
| VOC | -ū | -idē |
| CON/ESS | -ir, -ir- | -id, -id- |
1 The first and second forms of the topical and accusative case endings are mutually exclusive alternatives; the distribution is relatively even among the surviving texts.
An example noun is vokir "evil", declined as follows:
| CASE | sg. | pl. |
| NOM | vokir | vokidēs |
| TOP | voku, vokirou | vokidōi |
| ACC | voki, voku | vokidē |
| GEN | vokuris | vokidis |
| DAT | vokirae | vokidei |
| LOC | vokirum | vokidēm |
| ABL | vokirōn | vokidēn |
| INS | vokiritis | vokiditēs |
| VOC | vokū | vokidē |
| CON/ESS | vokir, vokir- | vokid, vokid- |
