Case

Meanings of the word case related to language have separate articles:

• upper and lower case, which are terms in printing; there is also the term title case used in computer formatting
• the grammatical term, case
• the confusion regarding the phrases in case of - in the case of

In areas of knowledge which are not specifically about academic writing in English, there are also two everyday meanings, each with many developments. (There is a note on the history of the word at case (etymology).)

The first has the basic meaning of 'an occurrence'. This is mostly used in present-day English to mean 'a particular example of' some sort of occurrence.

• In Medicine, a single patient is 'a case'. From this idea, we can now have a case study in many subject areas: the examination of one example of a phenomenon as an example or application of the general idea.
• In Law, a case is "a. A cause or suit brought into court for decision. b. A statement of the facts of any matter sub judice, drawn up for the consideration of a higher court ... d. The case as presented or 'put' to the Court by one of the parties in a suit; hence, the sum of the grounds on which he rests his claim. Also fig. as in to make out one's case, a case." (OED s.v. case, n.¹, 6).
• In popular literature, a 'case' may often be a particular event making a story for (usually) a criminal investigation, and the solution of a problem by a detective hero. (Conan Doyle's The Case-Book of Sherlock Holmes is a collection of such cases - though most of the chapters are called 'Adventures'.)

The second everyday meaning of case is based on the general idea of a 'container', or 'wrapper'. We pack clothes in a (suit)case; we can keep books in a bookcase; books themselves may be presented in hardcase or hardback, as opposed to paperback. A museum may show objects in a glass display case.