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case 1 (kās)
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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 case
1. 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 cāsus, from past participle of cadere, to fall; see kad- in the Appendix of Indo-European roots.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
 
case 2 (kās)
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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.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.