Vocative case

In grammar, the vocative case is a grammatical case which is used for a noun that identifies a person being addressed or occasionally for the noun modifiers of that noun. A noun of address is an expression of direct address by which the identity of the party spoken to is set forth expressly within a sentence. For example, in the sentence "I don't know, John," John is a noun of address that indicates the party being addressed, as opposed to the sentence "I don't know John", in which "John" is the direct object of the verb "know".
As observed by Zwicky, vocative case is used to express at least two functions: as a call aimed to attract the attention of an unratified overhearer, as address to maintain and perform the social relation towards the hearer.
Some authors including Gutzmann assume that so-called expressive vocatives are further distinct vocative function.
Historically, the vocative case was an element of the Indo-European case system and existed in Latin, Sanskrit, and Ancient Greek. In many modern Indo-European languages the vocative case has been absorbed by the nominative, but others still distinguish it, including the Baltic languages, some Celtic languages, Modern Greek and most Slavic languages. Some linguists, such as, argue that the vocative form is not a case but a special form of nouns not belonging to any case, as nouns of address are not related syntactically to other words in sentences. Pronouns usually lack vocative forms.

Indo-European languages

Comparison

Distinct vocative forms are assumed to have existed in all early Indo-European languages and survive in some. Here is, for example, the Indo-European word for "wolf" in various languages:
The elements separated with hyphens denote the stem, the so-called thematic vowel of the case and the actual suffix. In Latin, for example, the nominative case is lupus and the vocative case is lupe, but the accusative case is lupum. The asterisks before the Proto-Indo-European words means that they are theoretical reconstructions and are not attested in a written source. The symbol ◌̩ indicates a consonant serving as a vowel. All final consonants were lost in Proto-Slavic, so both the nominative and vocative Old Church Slavonic forms do not have true endings, only reflexes of the old thematic vowels.
Vocative singulars in Slavic languages appear to be irregular as a consequence of the Slavic first palatalization, which caused *k, *g and *x, when followed by an *e, to become č, ž, and š, respectively. Some modern Slavic languages have replaced these forms with a more regular vocative ending, so for example in Czech the usual masculine animate vocative is -e, except for roots ending in velar consonants, where it is now usually -u. This is an instance of the paradigmatic complexity introduced into Slavic by successive waves of palatalisation, with some languages retaining more complex or irregular paradigms, and others tending towards simplification and regularization.

Baltic languages

Lithuanian

The vocative is distinct in singular and identical to the nominative in the plural, for all inflected nouns. Nouns with a nominative singular ending in -a have a vocative singular usually identically written but distinct in accentuation.
In Lithuanian, the form that a given noun takes depends on its declension class and, sometimes, on its gender. There have been several changes in history, the last being the -ai ending formed between the 18th and 19th centuries. The older forms are listed under "other forms".
Some nouns of the e- and a- stems declensions are stressed differently: "aikštė": "aikšte!" ; "tauta": "tauta!". In addition, nouns of e-stems have an ablaut of long vowel ė in nominative and short vowel e in vocative. In pronunciation, ė is close-mid vowel, and e is open-mid vowel.
The vocative of diminutive nouns with the suffix -ukas most frequently has no ending: broliùk "brother!", etc. A less frequent alternative is the ending -ai, which is also slightly dialectal: broliùkai, etc.
Colloquially, some personal names with a masculine -o stem and diminutives with the suffixes -elis, -ėlis have an alternative vocative singular form characterized by a zero ending : Adõm "Adam!" in addition to Adõmai, Mýkol "Michael!" in addition to Mýkolai, vaikẽl "kid!" in addition to vaikẽli, etc.

Celtic languages

Goidelic languages

Irish

The vocative case in Irish operates in a similar fashion to Scottish Gaelic. The principal marker is the vocative particle a, which causes lenition of the following initial letter.
In the singular there is no special form, except for first declension nouns. These are masculine nouns that end in a broad consonant, which is made slender to build the singular vocative. Adjectives are also lenited. In many cases this means that masculine vocatives resemble the genitive and feminine vocatives resemble the nominative.
The vocative plural is usually the same as the nominative plural except, again, for first declension nouns. In the standard language first declension nouns show the vocative plural by adding -a. In the spoken dialects the vocative plural is often has the same form as the nominative plural or the dative plural

Scottish Gaelic

The vocative case in Scottish Gaelic follows the same basic pattern as Irish. The vocative case causes lenition of the initial consonant of nouns. Lenition changes the initial sound of the word.
In addition, masculine nouns are slenderized if possible This also changes the pronunciation of the word.
Also, the particle a is placed before the noun unless it begins with a vowel. Examples of the use of the vocative personal names :
The name "Hamish" is just the English spelling of Sheumais, and thus is actually a Gaelic vocative. Likewise, the name "Vairi" is an English spelling of Mhàiri, the vocative for Màiri.

Manx

The basic pattern is similar to Irish and Scottish. The vocative is confined to personal names, in which it is common. Foreign names are not used in the vocative. The vocative case causes lenition of the initial consonant of names. It can be used with the particle "y".
The name Voirrey is actually the Manx vocative of Moirrey.

Brythonic languages

Welsh

lacks case declension but marks vocative constructions by lenition of the initial consonant of the word, with no obligatory particle. Despite its use being less common, it is still used in formal address: the common phrase foneddigion a boneddigesau means "gentlemen and ladies", with the initial consonant of boneddigion undergoing a soft mutation; the same is true of gyfeillion in which cyfeillion has been lenited. It is often used to draw attention to at public notices orally and written – teachers will say "Blant" and signage such as one right show mutation of myfyrwyr to draw attention to the importance of the notice.

Germanic languages

English

The vocative is not a grammatical case in English. Expressions for which the vocative would be used in languages which have that case, are nominative in English. In translations of languages that use the vocative case, translators have sometimes added the particle "O" before the noun, as is often seen in the King James Version of the Bible: for example the Greek ὀλιγόπιστοι, vocative masculine plural, is translated "O ye of little faith". While it is not strictly archaic, it is sometimes used to "archaeise" speech; it is often seen as very formal, and sees use in rhetoric and poetry, or as a comedic device to subvert modern speech. Another example is the recurrent use of the phrase "O Best Beloved" by Rudyard Kipling in his Just So Stories. O may be considered a form of clitic and should not be confused with the interjection oh. However, as the Oxford English Dictionary points out, "O" and "oh" were originally used interchangeably.
Modern English commonly uses the objective case for nouns of address but sets them off from the rest of the sentences with pauses as interjections, rendered in writing as commas. Two common examples of nouns of address in English are the phrases "Mr. President" and "Madam Chairwoman".
Some traditional texts use Jesu, the Latin vocative form of Jesus. One of the best-known examples is Jesu, Joy of Man's Desiring.

German dialects

In some German dialects, like the Ripuarian dialect of Cologne, it is common to use the article before a person's name. In the vocative phrase then the article is, as in Venetian and Catalan, omitted. Thus, the determiner precedes nouns in all cases except the vocative. Any noun not preceded by an article or other determiner is in the vocative case. It is most often used to address someone or some group of living beings, usually in conjunction with an imperative construct. It can also be used to address dead matter as if the matter could react or to tell something astonishing or just happening such as "Your nose is dripping."
Colognian examples:

Do es der Päul — Päul, kumm ens erövver!	There is Paul. Paul, come over !
Och do leeven Kaffepott, do bes jo am dröppe!	O dear coffee pot, you are dripping!
„Pääde, jooht loufe!“ Un di Pääde jonn loufe.	"Horses, run away!" And the horses are running away.

Icelandic

The vocative case generally does not appear in Icelandic, but a few words retain an archaic vocative declension from Latin, such as the word wikt:Jesús#Icelandic, which is Jesú in the vocative. That comes from Latin, as the Latin for Jesus in the nominative is Jesus and its vocative is Jesu.
That is also the case in traditional English :

Nominative	Jesús elskar þig.	Jesus loves you.
Vocative	Ó Jesú, frelsari okkar.	O Jesus, our saviour.

The native words wikt:sonur#Icelandic and wikt:vinur#Icelandic also sometimes appear in the shortened forms son and vin in vocative phrases. Additionally, adjectives in vocative phrases are always weakly declined, but elsewhere with proper nouns, they would usually be declined strongly:

strong adjective, full noun	Kær vinur er gulli betri.	A dear friend is better than gold.
weak adjective, shortened noun	Kæri vin, segðu mér nú sögu.	Dear friend, tell me a story.