Lesson 3 – Second declension nouns, to be

Second declension nouns

  • The largest group is masculine and ends in ‘-us’, ‘-er’ or ‘-ir’
  • Some are neuter and end in ‘-um’

Masculine ‘-us’ ending

These are declined with these endings:

Case Singular Plural
Nominative -us -i
Vocative -e or -i -i
Accusative -um -os
Genitive -i -orum
Dative -o -is
Ablative -o -is

Look at our example of dominus, lord, sir, the Lord.

Case Singular Plural
Nominative dominus domini
Vocative domine domini
Accusative dominum dominos
Genitive domini dominorum
Dative domino dominis
Ablative domino dominis

More second declension masculine nouns:

annus year
deus God
filius son

Men’s names often belong to the second declension:

Gregorius Gregory
Henricus Henry
Stephanus Stephen
Willelmus William

Here are some sentences showing you how the new words are used:

dominus terram legat The lord bequeaths land
terra domini The land of the lord
Deo et ecclesie lego I leave to God and the Church
Henrico confirmo I confirm to Henry
Willelmus terram Gregorii dat William gives the land of Gregory
dominus et domina terram Deo et ecclesie confirmant The lord and the lady confirm the land to God and the Church
anno domini in the year of [our] Lord anno is ablative and here means ‘in the year’; domini is genitive

Vocative singular is the same as the nominative except in second declension nouns

  • Ending ‘-us’ – when the vocative ends with an ‘-e’
  • Ending ‘-ius’ in names like Gregorius – vocative ends with an ‘-i’


Often abbreviated to AD, anno domini is used in the Christian calendar to express dates after the birth of Jesus.

Masculine ‘-er’ ending

These take the same endings as masculine ‘-us’ ending nouns except

  • Nominative singular ends in ‘-er’
  • Vocative singular is the same as the nominative

You will only come across these four words. They are declined in the ‘Nouns’ resource.

armiger esquire
faber smith
magister master, teacher
puer boy

They can be divided into two groups.

puer and armiger which always keep their ‘e’ when they are declined.

magister and faber. When they are declined, they only keep the ‘e’ of the ‘er’ in the nominative and vocative singular cases.

For example

faber terras legat The smith bequeaths lands

In this sentence, faber has an ‘e’ because it is in the nominative case.

cartas magistro Stephano confirmo I confirm charters to master Stephen

Whereas in this sentence, magister has lost its ‘e’, because it is in the dative case.


Thinking of related English words may help you remember this: magistrate and fabricate do not have an ‘e’.

Masculine ‘-ir’ ending

‘vir’ man, husband

The only second declension noun ending ‘ir’. It is fully declined in the grammar table.

Neuter ‘-um’ ending

These are declined with these endings:

Case Singular Plural
Nominative -um -a
Vocative -um -a
Accusative -um -a
Genitive -i -orum
Dative -o -is
Ablative -o -is

Look at our example of regnum reign

Case Singular Plural
Nominative regnum regna
Vocative regnum regna
Accusative regnum regna
Genitive regni regnorum
Dative regno regnis
Ablative regno regnis

These are more neuter nouns:

mercatum market
testamentum will, testament
regnum regine Marie the reign of Queen Mary

Some neuter nouns that end in ‘um’ have a stem that ends in ‘i’

escambium exchange
manerium manor
Westmonasterium Westminster

They decline in the same way but keep the ‘i’.

dominus manerii The lord of the manor
Stephanus maneria carta confirmat Stephen confirms the manors by charter

Handy hints

Learn noun endings quickly by looking for patterns:

  1. Nominative and vocative endings are always the same except for second declension nouns ending in ‘-us’.
  2. Nominative and accusative cases of neuter nouns are always the same. The plural always ends in ‘-a’.
  3. Accusative singular for masculine and feminine nouns always ends in ‘-m’; accusative plural for masculine and feminine nouns always ends in ‘-s’.
  4. Genitive plural of all declensions ends in ‘-um’.
  5. Dative and ablative plurals are always the same. In the first and second declensions, the ending is usually ‘-is’.

esse – to be

This is an irregular verb, both in English and in Latin, as it does not follow the usual patterns of conjugation.

Latin Means in English
sum I am
es you are (singular)
est he/she/it is
sumus we are
estis you are (plural)
sunt they are

esse does not have an object. Words associated with it are in the nominative case. Don’t try to put them into the accusative.

vir sum I am a man
dominus est He is the lord
testamentum est It is the will
Isabella et Maria sumus We are Isabella and Mary
agricole sumus We are the farmers (nominative plural as there is more than one)
vidue sunt They are the widows (nominative plural as there is more than one)
Isabella regina est. Isabella is the queen

Both Isabella and regina must be in the nominative

domine regine sunt The ladies are queens
Maria et Isabella regine sunt Mary and Isabella are queens.

In this example, Maria and Isabella are nominative singular, as there is one of each woman. regine is nominative plural as there are two queens.

Medieval names

Men’s names often include the phrase ‘son of’:

Henricus filius Willelmi  Henry son of William
Willelmus filius Henrici William son of Henry
cartas Willelmo filio Stephani do I give charters to William son of Stephen

Willelmo and filio are both in the dative case because the charters are given to him.

Stephani stays in the genitive, because William is the son of Stephen.


Are you confident with:

  • how to decline a second declension noun like magister?
  • how to decline a second declension noun like dominus?
  • how to decline a second declension noun like testamentum?
  • the handy hints for declining nouns?
  • how to conjugate ‘to be’ in Latin?
  • whether esse has an object?

What next?