Case refers to the formal markers (in Latin they are endings added to the stem of a noun or adjective) that tell you how a noun or adjective is to be construed in relationship to other words in the sentence. What are the formal markers for English? Here are some reflections on how cases in general relate to meaning in a sentence.
There are 6 distinct cases in Latin: Nominative, Genitive, Dative, Accusative, Ablative, and Vocative; and there are vestiges of a seventh, the Locative. The basic descriptions that follow are also found on the pages introducing the more detailed descriptions of the cases, which you may reach by clicking the case names in the prior sentence.
The nominative case is the case for the subject of the sentence. The subject is the person or thing about which the predicate makes a statement, and the name, "nominative," means "pertaining to the person or thing designated." In Latin the subject does not always need to be expressed because it can be indicated by the person and number of the verb. "They praise" = laudant. See the subject case in English, which is similar to the Latin nominative case. Go to: Nominative Case
The genitive case is most familiar to English speakers as the case that expresses possession: "my hat" or "Harry's house." In Latin it is used to indicate any number of relationships that are most frequently and easily translated into English by the preposition "of": "love of god", "the driver of the bus," the "state of the union," "the son of god." The genitive case in Latin is also used adverbially with certain verbs. The most common are verbs of convicting, accusing and punishing. The construction is parallel to the English "I accuse you of treason." accuso te maiestatis. See how the possessive case and the preposition "of" work in English. To see a more detailed list of the Go to: Genitive Case.
The dative case is most familiar to English speakers as the case of the indirect object, and the most common instance of the indirect object is the person "to or for whom" something is given: "I gave the book to her", "to her" would be in the dative case. This common usage gives the case its name: it is the case that pertains to giving. However, it is more satisfactory to consider the dative case as the case for the person who is interested (in a positive or negative way) in some action or activity, and the most common (and most accurate) translation of the dative case is "for." Consider: as I give the book, I might say "for you." This indicates that even in the idiom "I give the book to you", the giving itself is really "for you." The dative is common after verbs that indicate certain kinds of activities: favoring, obeying, pleasing, serving, envying, being angry, pardoning, ordering, and so on.Go to: Dative Case
The accusative case is the case for the direct object of transitive verbs, the internal object of any verb (but frequently with intransitive verbs), for expressions indicating the extent of space or the duration of time, and for the object of certain prepositions. Originally it was the case that indicated the end or ultimate goal of an action. Go to: Accusative Case.
The ablative case is the most complex of the cases in Latin. It may be used by itself or as the object of prepositions and it is commonly used to express (with or without the aid of a preposition) ideas translated into English by the prepositions "from" (that is, an idea of separation and origin), "with" and "by" (that is, an idea of instrumentality or association), and "in" (that is, an idea of place where or time when). Go to: Ablative Case.
The vocative case presents little problem for English speakers. It is usually the same as the nominative, as in English, and it is used when you address someone directly. The exceptions to the rule that the vocative is the same as the nominative are summarized in the phrase, Marce mi fili, which is the vocative for Marcus meus filius, and is a convenient way to remember that all 2nd declension nouns in -us, have a vocative in -e, that the vocative of meus is mi, and that all 2nd declension nouns in -ius have a vocative in -i.
Latin also had a Locative Case, but few of the forms are still used in Classical Latin. The locative case is used to indicate "place where" and is found primarily with the names of cities, towns and small islands. (Actually, these three places are all the same since the island has to be small enough to be named for the only city or town on it; if there are two towns, you much use in + Ablative. The forms for the Locative are the same as the genitive in the 1st and 2nd Declension Singular and the same as the Ablative in the 3rd Declension Singular. Towns (like Athens, Athenae) whose form is plural take their locative forms from the Ablative plural in all declensions. Other locative forms are: domi, humi, belli, militiae, and ruri.