The term "noun cases" is correct and can be used in written English.
It refers to the different forms or inflections that a noun can take depending on its grammatical role in a sentence. Example: In the sentence "The dog chased the cat," "dog" is in the nominative case as the subject, while "cat" is in the accusative case as the direct object.
Only relatively recently did grammarians begin a debate over noun cases in English.
The noun cases were further reduced, and the introduction of nominal (noun) forms into the verb system became more pronounced.
Luckily, however, they both share a third quality, "paucity of inflection" – less of the "chaos" of noun cases and verb endings than many other languages.
As a consequence, English was often described until well into the 20th century as having six different noun cases, because Latin has six.
Some now contend that it does not have noun cases at all, others that it has two onee for the possessive, the other for everything else) while still others maintain that there are three or four cases.
The modern language has seven noun cases, two numbers, three persons in the verb, three tenses (present, past, and future), two voices, and three moods (indicative, imperative, and conditional or subjunctive), and it marks verbs for perfective (completed action) and imperfective (action in process or uncompleted action) aspects.
The nominative (subject noun) case is not represented by any suffix.
(A noun case is how that noun's grammatical use is distinguished, for example as a subject or as an object).
Modern Welsh, like English, makes very little use of inflectional endings; British, the Brythonic language from which Welsh is descended, was, however, an inflecting language like Latin, with word endings marking such grammatical categories as noun case and verb tense.
Inflection (i.e., the use of endings, prefixes, and vowel alternations) has persisted as the main method of differentiating grammatical meanings, although to a lesser degree in nouns than in verbs because many functions of the noun case endings may also be expressed by prepositions.
The interpretation of this pattern might reflect a longer continuation of the same process in the common noun case, or it might reflect an additional later process that is not invoked in the proper noun case.
