case 1 (k?s)n.1. An instance or occurrence of a particular kind or category: a case of mistaken identity. See Synonyms at example.2. An occurrence of a disease or disorder: a mild case of flu.3. A set of circumstances or a state of affairs; a situation: It may rain, in which case the hike will be canceled.4. Actual fact; reality: We suspected the walls were hollow, and this proved to be the case.5. A question or problem; a matter: It is simply a case of honor.6. A situation that requires investigation, especially by a formal or official body.7. Law a. An action or a suit or just grounds for an action.b. The facts or evidence offered in support of a claim.8. A set of reasons or supporting facts; an argument: presented a good case for changing the law.9. A person being assisted, treated, or studied, as by a physician, lawyer, or social worker.10. Informal A peculiar or eccentric person; a character.11. Linguistics a. In traditional grammar, a distinct form of a noun, pronoun, or modifier that is used to express one or more particular syntactic relationships to other words in a sentence.b. Case In some varieties of generative grammar, the thematic or semantic role of a noun phrase as represented abstractly but not necessarily indicated overtly in surface structure. In such frameworks, nouns in English have Case even in the absence of inflectional case endings.Idioms: in any case Regardless of what has occurred or will occur. in case1. If it happens that; if: In case she dies without heirs, her money will go to charity.2. To be prepared for the possibility that: bring the charger in case the battery runs low.3. As a precaution: took along an umbrella, just in case. in case of If there should happen to be: a number to call in case of emergency. off (someone’s) case No longer nagging or urging someone to do something. on (someone’s) case Persistently nagging or urging someone to do something.[Middle English cas, from Old French, from Latin c?sus, from past participle of cadere, to fall; see kad- in Indo-European roots.]case 2 (k?s)n.1. A container; a receptacle: a jewelry case; meat-filled cases of dough.2. A container with its contents.3. A decorative or protective covering or cover.4. A set or pair: a case of pistols.5. The frame or framework of a window, door, or stairway.6. The surface or outer layer of a metal alloy.7. Printing a. A shallow compartmented tray for storing type or type matrices.b. The form of a written, printed, or keyed letter that distinguishes it as being lowercase or uppercase: typed the password using the wrong case.tr.v. cased, cas·ing, cas·es 1. To put into or cover with a case; encase.2. Slang To examine carefully, as in planning a crime: cased the bank before robbing it.[Middle English, from Norman French casse, from Latin capsa.]American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.