Editing Latin declension (section)

== Peculiarities within declension ==

=== Irregularity in number ===
Some nouns are only used in the singular ([[plurale tantum#Singulare tantum|singulare tantum]]) such as:
* materials, such as {{wikt-lang|la|aurum}} 'gold'
Some nouns are only used in the plural ([[plurale tantum]]), or when plural have a singular meaning such as:
* many festivals, such as {{wikt-lang|la|Saturnālia}} '[[Saturnalia]]'
* {{wikt-lang|la|castra}} 'camp' and {{wikt-lang|la|arma}} 'arms'; {{wikt-lang|la|littera|litterae}} 'a letter' (cf. {{lang|la|littera}} 'letter of the alphabet')
* a few geographical names are plural such as {{wikt-lang|la|Thēbae}} 'Thebes' (both the [[Thebes, Greece|Greek]] and the [[Thebes, Egypt|Egyptian]] cities)

=== Indeclinable nouns ===
Indeclinable nouns are nouns which only have one form in all cases (of the singular).
* {{wikt-lang|la|fās}} ('[[Glossary of ancient Roman religion#fas|divine law]]')
* {{wikt-lang|la|īnstar}} ('likeness')
* {{wikt-lang|la|māne}} ('morning')
* {{wikt-lang|la|nefās}} ('[[nefas|sin, abomination]]')
* {{wikt-lang|la|secus}} ('(male or female) sex')

=== Heterogeneous nouns ===
Heterogeneous nouns are nouns which vary in respect to gender.

* A few nouns in the second declension occur in both the neuter and masculine. However, their meanings remain the same.
* Some nouns are one gender in the singular, but become another gender in the plural. They may also change in meaning.

{| class=wikitable
! Singular !! Plural
|-
| {{wikt-lang|la|balneum}} {{abbr|n.|neuter}} ('bath') || ''balneae'' {{abbr|f.|feminine}} or ''balnea'' {{abbr|n.|neuter}} ('bathhouse')
|-
| {{wikt-lang|la|epulum}} {{abbr|n.|neuter}} ('feast, banquet') || ''epulae'' {{abbr|f.|feminine}} ('feast, banquet')
|-
| {{wikt-lang|la|frēnum}} {{abbr|n.|neuter}} ('bridle, curb') || ''frēnī'' {{abbr|m.|masculine}} bridle, curb
|-
| {{wikt-lang|la|iocus}} {{abbr|m.|masculine}} ('joke, jest') || ''ioca'' {{abbr|n.|neuter}} or ''ioci'' {{abbr|m.|masculine}} ('jokes, fun')
|-
| {{wikt-lang|la|locus}} {{abbr|m.|masculine}} ('place, location') || ''loca'' {{abbr|n.|neuter}} ('region'); ''locī'' {{abbr|m.|masculine}} ('places in books, arguments')
|-
| {{wikt-lang|la|rāstrum}} {{abbr|n.|neuter}} ('hoe, rake') || ''rāstrī'' {{abbr|m.|masculine}} ('hoes, rakes')
|}

=== Plurals with alternative meanings ===
{| class=wikitable
! Singular !! Plural
|-
| {{wikt-lang|la|aedes|aedēs, aedis}} {{abbr|f.|feminine}} ('building, temple') || {{wikt-lang|la|aedes|aedēs, aedium}} ('rooms, house')
|-
| {{wikt-lang|la|auxilium|auxilium, auxiliī}} {{abbr|n.|neuter}} ('help, aid') || {{wikt-lang|la|auxilia|auxilia, auxiliōrum}} ('auxiliary troops')
|-
| {{wikt-lang|la|carcer|carcer, carceris}} {{abbr|m.|masculine}} ('prison, cell') || {{wikt-lang|la|carceres|carcerēs, carcerum}} ('starting traps')
|-
| {{wikt-lang|la|castrum|castrum, castrī}} {{abbr|n.|neuter}} ('fort, castle, fortress') || {{wikt-lang|la|castra|castra, castrōrum}} ('military camp, encampment')
|-
| {{wikt-lang|la|copia|cōpia, copiae}} {{abbr|f.|feminine}} ('plenty, much, abundance') || {{wikt-lang|la|copiae|cōpiae, copiārum}} ('troops')
|-
| {{wikt-lang|la|fortuna|fortūna, fortūnae}} {{abbr|f.|feminine}} ('luck, chance') || {{wikt-lang|la|fortunae|fortūnae, fortūnārum}} ('wealth, fortune')
|-
| {{wikt-lang|la|gratia|grātia, grātiae}} {{abbr|f.|feminine}} ('charm, favor') || {{wikt-lang|la|gratiae|grātiae, grātiārum}} ('thanks')
|-
| {{wikt-lang|la|impedimentum|impedīmentum, impedīmentī}} {{abbr|m.|masculine}} ('impediment, hindrance') || {{wikt-lang|la|impedimenta|impedīmenta, impedīmentōrum}} ('baggage, baggage train')
|-
| {{wikt-lang|la|littera|littera, litterae}} {{abbr|f.|feminine}} ('letter [alphabet]') || {{wikt-lang|la|litterae|litterae, litterārum}} ('letter [message], epistle, scholarship, literature')
|-
| {{wikt-lang|la|mos|mōs, mōris}} {{abbr|m.|masculine}} ('habit, inclination') || {{wikt-lang|la|mores|mōrēs, mōrum}} {{abbr|m.|masculine}} ('morals, character')
|-
| {{wikt-lang|la|opera|opera, operae}} {{abbr|f.|feminine}} ('trouble, pains') || {{wikt-lang|la|operae|operae, operārum}} {{abbr|m.|masculine}} ('workmen')
|-
| {{wikt-lang|la|opis|*ops, opis}} {{abbr|f.|feminine}}{{efn-lr|Nominative and dative are not attested except as the name of the goddess [[Ops]].}} ('help') || {{wikt-lang|la|opes|opēs, opium}} ('resources, wealth')
|-
| {{wikt-lang|la|pars|pars, partis}} {{abbr|f.|feminine}} ('part, piece') || {{wikt-lang|la|partes|partēs, partium}} ('office, function')
|}
{{notelist-lr}}