Appendix:Latin third declension

Nouns

general rule: Parisyllables and Imparisyllables

Third Declension

Cases	Declension Imparisyllables				Declension Parisyllables
	Masculine/Feminine		Neuter		Masculine/Feminine		Neuter
	Singular	Plural	Singular	Plural	Singular	Plural	Singular	Plural
Nominative	---	-es	---	-a	---	-es	---	-ia
Vocative	---	-es	---	-a	---	-es	---	-ia
Accusative	-em	-es	---	-a	-em	-es	---	-ia
Genitive	-is	-um	-is	-um	-is	-ium	-is	-ium
Dative	-i	-ibus	-i	-ibus	-i	-ibus	-i	-ibus
Ablative	-e	-ibus	-e	-ibus	-e	-ibus	-i	-ibus

• Parisyllabic, nouns that have an equal number of syllables in the nominative and in the genitive singular (e.g. nom. civis, gen. civis).
• Imparisyllables, nouns that do not have an equal number of syllables in the nominative and in the genitive singular (e.g. nom. consul, gen. consulis).
• In some "imparisyllabic" the genitive plural is in "ium" est: lis, litis; dos, dotis; mus,muris; etc.
• In some cases the accusative singular in "-im" and the ablative singular in "-i" are: turris,-is; puppis,-is; sitis,-is; vis,-is; tussis,-is; securis,-is; febris,-is.
• "Animal, -is"; "calcar,-is" and other neuter nouns that end in "-al/-ar" are considered as parisyllables.

Description

Latin nouns of the third declension comprise consonant stems and i-stems (e.g., as the i in the neutral genitive plural animalium). They are of all three genders, and have genitives in -is. The forms of the nominative and vocative singular are identical to each other and are often quite different from other cases, in which case both stems are given in citation forms.

Words borrowed from Greek's third declension are inflected with a varying mixture of Greek and Latin case endings.

Examples

Consonant stem

Citation form: homō, hominis m

Case	Singular	Plural
nominative	homō	homin·ēs
genitive	homin·is	homin·um
dative	homin·ī	homin·ibus
accusative	homin·em	homin·ēs
ablative	homin·e	homin·ibus
vocative	homō	homin·ēs
locative	homin·e (-ī)	homin·ibus

Neuter consonant stem

Citation form: nōmen, nōminis n

Case	Singular	Plural
nominative	nōmen	nōmin·a
genitive	nōmin·is	nōmin·um
dative	nōmin·ī	nōmin·ibus
accusative	nōmen	nōmin·a
ablative	nōmin·e	nōmin·ibus
vocative	nōmen	nōmin·a
locative	nōmin·ī	nōmin·ibus

i-stem

Citation form: turris, turris f

Case	Singular	Plural
nominative	turris	turrēs
genitive	turris	turrium
dative	turrī	turribus
accusative	turrem (-im)	turrēs (-īs)
ablative	turre (-ī)	turribus
vocative	turris	turrēs
locative	turrī	turribus

"Pure" i-stem

Citation form: animal, animālis n

Case	Singular	Plural
nominative	animal	animālia
genitive	animālis	animālium
dative	animālī	animālibus
accusative	animal	animālia
ablative	animālī	animālibus
vocative	animal	animālia
locative	animālī	animālibus

Mixed declension (mixed i-stem)

Citation form: nox, noctis f

Case	Singular	Plural
nominative	nox	noctēs
genitive	noctis	noctium
dative	noctī	noctibus
accusative	noctem	noctēs
ablative	nocte	noctibus
vocative	nox	noctēs
locative	noctī	noctibus

Greek declensions

Declesion general

Citation form: āēr, āeris m, sometimes f

Case	Singular	Plural
nominative	āēr	āer·ēs
genitive	āer·is / āer·os	āer·um
dative	āer·ī	āer·ibus
accusative	āer·a / āer·em	āer·ēs
ablative	āer·e	āer·ibus
vocative	āēr	āer·ēs
locative	āer·ī	āer·ibus

Citation form: tigris, tigridis m and f

Case	Singular	Plural
nominative	tigris	tigr·ēs / tigrid·ēs
genitive	tigrid·is / tigr·is / tigrid·os	tigr·ium
dative	tigrid·ī / tigr·ī	tigr·ibus
accusative	tigr·im / tigr·in	tigr·is / tigrid·as
ablative	tigrid·e / tigr·ī	tigr·ibus
vocative	tigris	tigr·ēs / tigrid·ēs
locative	tigrid·ī / tigr·ī	tigr·ibus

Similiar to i-stem declension:

Case	Singular	Plural
nominative	-is	-es
genitive	-is; -os; -eos	-ium; -eon
dative	-i	-ibus
accusative	-im; -in	-is, -es; -eis
ablative	-i	-ibus
vocative	-is	-es

Examples:

• haeresis, -eos, f.; basis, -is and -eos, f.; tigris, -is, m. and f.

For feminine proper nouns from Greek in -ō with genitive in -ūs, see Appendix:Latin fourth declension § Feminine -ō form (from Greek).

five types of Greek nouns third declension

Excluding proper nouns, there seem to be around 4-5 types of declensions of greek nouns as part of Latin's 3rd declension:

1. in -ō, like ēchō, -ūs, f.

• Gen. sg. -ûs, all other singular cases -ô. Plural isn't mentioned in the sources above, thus should be regular (e.g. êchês in nom.pl.)
• echo is said to be in 3rd declension - not in 4 as it's here at Wiktionary.
• Georges mentions acc. sg as -ōn for êchô.
• Like Dîdô it might also be -onis, -onî, -onem, -one (gen., dat., acc., abl. sg.).
• Maybe some of these words were addopted like Latin words in -o, -onis, f.

2. chaos, epos, melos - n.

• It's commonly said that some cases are missing or were missing in antique times.

Case	n.
Singular
Nom.	-os
Gen.	-i; -us
Dat.	-o; -i
Acc.	-os
Abl.	-o
Voc.	-os
Plural
Nom.	-ē (-ea)
Gen.	-um
Dat.	-ibus
Acc.	-ē
Abl.	-ibus
Voc.	-ē

There are 3 declension variants: 1. more like Greek declension; 2. influenced by Latin's second declension and 3. changed to masculine words like Latin's second declension (e.g. cētus, -i, m. from cētos, -us, n. = (τό) κῆτος).

3. chelys (f.)

• It is similar to the variant that is similar to i-stem declension (see below), but often without i, e.g.: acc.sg. as -n instead of -in added to chely-, or acc.sg. as -yn instead of -in added to chel-.
• Instead of e.g. -ibus in dat.&abl. pl. it might also be chelybus (Lewis Marcus).
• Somewhere forms like chelin instead of chelyn were mentioned.

4. Like i-declension

Case	m./f.
	Singular
Nom.	-is
Gen.	-is; -eos, -ios
Dat.	-ī
Acc.	-im; -in
Abl.	-ī
Voc.	-is (-i)
Case	Plural
Nom.	-ēs
Gen.	-ium; -eōn
Dat.	-ibus
Acc.	-īs, -ēs
Abl.	-ibus
Voc.	-ēs

• Vowel lengths: Gen. sg.: In older English works (A&G, L&S) it is -eōs instead of -eos. Allen & Greenough and Lewis & Short have -eōs; Lewis Marcus, Georges, Pons have -eos. As Georges and Pons are newer than A&G and L&S, it seems more reliable (cf. stēlla in contrary to stella).
• Examples: haeresis, basis (acc. pl. also -e͡is and accourding to Lewis Marcus with other irregular forms), tigris (gen. sg. -is), poēsis (poësis)

5. Like consonantic declension

Cases	m./f.	or ys, m./f.	n.
	Singular
Nom.	~(s)/~(ēr)/~(n)	~(ys)	-a
Gen.	-is; -os ‡¹
Dat.	-ī; (-i)
Acc.	-em; -a		-a
Abl.	-e
Voc.	~(s)/~(ēr)/~(n)	(~ys), -y	-a
Kasus	Plural
Nom.	-ēs; -es		-a
Gen.	-um		-um & -orum
Dat.	-ibus; ‡²		-ibus & -is
Acc.	-ēs; -as (-es) ‡³		-a
Abl.	-ibus; ‡²		-ibus & -is
Voc.	-ēs; -es		-a

• ‡¹ (especially) by words with gen. sg. in dis it is also dos
• ‡² a) Accourding to Lewis Marcus some words have the ending is resp. -isi and -ibus, e.g. heroisi from heros. b) Weyh writes that dat. pl. can be -si and -sin (example: ethesi), and Georges and Lewis & Short have abl. pl. ethesin of ēthos. "herosi" can be found, it's e.g. in [books.google.de/books?id=sGMTAAAAYAAJ&pg=PA265 Prisciani Caesariensis Grammatici Opera] ("non herosi [...] herosi"). c) ἥρως#Ancient Greek is like herosi[n] in dat. pl. Thus -si[n] in dat. and abl. pl. makes sense, but heroisi seems wrong. -- Maybe pure Greek declensions (in singular and plural) + (old) transcription into Latin should be added, so one can see what might be possible. (?)
• ‡³ (at least )some words have -es and -ēs/-as
• Words of neuter gender have forms of the 3rd and of the 2nd declension in plural. Well, poēma/poëma has those forms, but that could also be an exception.

Examples:

• hērōs, adamās (also adamāns), lebēs (Greek-like acc. pl. with -es and -as)
• lampas (Greek-like acc. pl. with -es and -as), tigris (-idis; having the forms of tigris, -is in gen. sg. and nom., gen., dat. and abl. pl.), delphīn (also delphīs)
• pēlamys, chlamys
• crāter, āēr
• poēma (poëma), n.

Adjectives

Description

Latin nouns of the third declension comprise consonant stems and i-stems. The consonant stems include the comparative form of adjectives. This declension is divided into three subcategories: adjectives of one termination (which includes present participles), adjectives of two terminations (one for m and f, and one for n), and adjectives of three terminations (which are generally -er m, -ris f and -re n).

Examples

One-termination consonant stem

Citation form: vetus, -eris

Case	m f singular	n singular	m f plural	n plural
nominative	vetus	vetus	veter·ēs	veter·a
genitive	veter·is	veter·is	veter·um	veter·um
dative	veter·ī	veter·ī	veter·ibus	veter·ibus
accusative	veter·em	vetus	veter·ēs	veter·a
ablative	veter·e	veter·e	veter·ibus	veter·ibus
vocative	vetus	vetus	veter·ēs	veter·a
locative	veter·ī	veter·ī	veter·ibus	veter·ibus

One-termination i-stem

Citation form: atrōx, -ōcis

Case	m f singular	n singular	m f plural	n plural
nominative	atrōx	atrōx	atrōc·ēs	atrōc·ia
genitive	atrōc·is	atrōc·is	atrōc·ium	atrōc·ium
dative	atrōc·ī	atrōc·ī	atrōc·ibus	atrōc·ibus
accusative	atrōc·em	atrōx	atrōc·ēs, ·īs	atrōc·ia
ablative	atrōc·ī	atrōc·ī	atrōc·ibus	atrōc·ibus
vocative	atrōx	atrōx	atrōc·ēs	atrōc·ia
locative	atrōc·ī	atrōc·ī	atrōc·ibus	atrōc·ibus

Two-termination consonant stem (comparatives)

Citation form: melior, -us

Case	m f singular	n singular	m f plural	n plural
nominative	melior	melius	meliōr·ēs	meliōr·a
genitive	meliōr·is	meliōr·is	meliōr·um	meliōr·um
dative	meliōr·ī	meliōr·ī	meliōr·ibus	meliōr·ibus
accusative	meliōr·em	melius	meliōr·ēs	meliōr·a
ablative	meliōr·e	meliōr·e	meliōr·ibus	meliōr·ibus
vocative	melior	melius	meliōr·ēs	meliōr·a
locative	meliōr·ī	meliōr·ī	meliōr·ibus	meliōr·ibus

Two-termination i-stem

Citation form: tristis, -e

Case	m f singular	n singular	m f plural	n plural
nominative	trist·is	trist·e	trist·ēs	trist·ia
genitive	trist·is	trist·is	trist·ium	trist·ium
dative	trist·ī	trist·ī	trist·ibus	trist·ibus
accusative	trist·em	trist·e	trist·ēs, -īs	trist·ia
ablative	trist·ī	trist·ī	trist·ibus	trist·ibus
vocative	trist·is	trist·e	trist·ēs	trist·ia
locative	trist·ī	trist·ī	trist·ibus	trist·ibus

See also

• Latin first declension
• Latin second declension
• Latin fourth declension
• Latin fifth declension
• Wikipedia article on declension
• Wikipedia article on Latin declension