Despite Skaran no longer having a purely Latin base—as detailed in the article in my signature, it still uses Latin conjugation and declension tables. How could the Romans declined a III declension noun ending in -n, like Faχυn (fachun), meaning military police?
It's your fantasy world - make them whatever you want.
Remind me - is this for a novel you're trying to sell?
I've heard the best approach for something like that is to write an outline and just a short sample of your writing. Try to sell that to the publisher, rather than write a full length novel (plus all the backstory/language development) and try to sell that.
WORDS has the following:
For 3rd declension ending in -an, add -is in the genitive: paean, paeanis.
For 3rd declension ending in -en, the usual form is to drop the -en and add -inis: abdomen, abdominis.
Less frequent is to add an -is in the genitive: ren, renis - kidney.
For 3rd declension ending in -in, add -is in the genitive: delphin, delphinis.
For 3rd declension ending in -on, the usual form is to add -is: aeon, aeonis.
Less frequent is to add -tis: bison, bisontis.
There are no 3rds ending in -un or -yn.
Nouns borrowed from Greek have an alternate -os ending in the genitive singular: horizon, horizontos/horizontis. mammon, mammos/is is listed but I believe that to be a mistake.
For reference purposes, Skaran has the following consonants: b, γ (g), d, h, θ (th), μ (j), k, l, m, n, p, r, s, t, u (w), ξ (ks), z, χ (ch), ψ (ps), and σ (sh). Skaran has five declensions, which are listed below with the nouns I have for them. Like Latin, Skaran doesn't distinguish between proper nouns and regular nouns. The adjectives I have are below as well. Which would have a locative case?
Nouns I declension (-a, -a+consonant, -á, -á+consonant, é, é+consonant) (Greek/Latin I decl. table)
No examples needed
II declension(ω-stem; -ω, -ω+consonant, -ώ, -ώ+consonant) (ancient Greek II decl. table with Latin ablatives/locatives)
No examples needed
III declension(-e, e+consonant-i, -i+consonant, -í, -í+consonant) (table needed)
IV declension (υ-stem; -υ, -υ+consonant, -ύ, -ύ+consonant) (table needed)
Δώndύ (Navy), Kelsiυm, and Téώlanυs (Thunderbolt) (differs from "lightning")
V declension (consonant-stem) (table needed; possibility Latin consonant-stem tables)
No examples yet
Uncertain declension Faχωn (II) or Faχυn (IV) (Military Police)
To the mods (Iojannes, etc.): Please make the following changes to the above post:
1. (a) (table needed) to Latin (IV decl. table(s)) and (b) Δώndύ (Navy), Kelsiυm, and Téώlanυs (Thunderbolt) (differs from "lightning") to Question: are all IV declension Latin nouns inanimate?, and
2. (a) (table needed) to Latin (III decl. consonant-stem tables) and (b) No examples yet to No examples needed.
Also, do -is (m./f.)/-e (nt.) adjectives (návális, etc.) ever refer to living things?