cause

¹ American  

[kawz] / kɔz /

noun

1. a person or thing that acts, happens, or exists in such a way that some specific thing happens as a result; the producer of an effect.

   You have been the cause of much anxiety.

   What was the cause of the accident?

2. the reason or motive for some human action.

   The good news was a cause for rejoicing.

3. good or sufficient reason.

   to complain without cause;

   to be dismissed for cause.

4. Law.

   1. a ground of legal action; the matter over which a person goes to law.

   2. a case for judicial decision.

5. any subject of discussion or debate.

6. a principle, ideal, goal, or movement to which a person or group is dedicated.

   the Socialist cause;

   the human rights cause.

7. the welfare of a person or group, seen as a subject of concern.

   support for the cause of the American Indian.

8. Philosophy.

   1. the end or purpose for which a thing is done or produced.

   2. Aristotelianism. any of the four things necessary for the movement or the coming into being of a thing, namely a material material cause, something to act upon it efficient cause, a form taken by the movement or development formal cause, and a goal or purpose final cause.

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verb (used with object)

caused, causing

1. to be the cause of; bring about.

   Synonyms:

   produce, create, make, effect

idioms

1. make common cause, to unite in a joint effort; work together for the same end.

   They made common cause with neighboring countries and succeeded in reducing tariffs.

'cause ² American  

[kawz, kuhz, kuhz] / kɔz, kʌz, kəz /

conjunction

Informal.

1. a shortened form of because.

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cause British  

/ kɔːz /

noun

1. a person, thing, event, state, or action that produces an effect

2. grounds for action; motive; justification

   she had good cause to shout like that

3. the ideals, etc, of a group or movement

   the Communist cause

4. the welfare or interests of a person or group in a dispute

   they fought for the miners' cause

5. a matter of widespread concern or importance

   the cause of public health

6. 1. a ground for legal action; matter giving rise to a lawsuit

   2. the lawsuit itself

7. (in the philosophy of Aristotle) any of four requirements for a thing's coming to be, namely material (material cause), its nature (formal cause), an agent (efficient cause), and a purpose (final cause)

8. to join with (a person, group, etc) for a common objective

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verb

1. (tr) to be the cause of; bring about; precipitate; be the reason for

cause More Idioms  

More idioms and phrases containing cause

• lost cause

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Usage

What is a basic definition of cause? A cause is a person, thing, event, or action that triggers a resulting event. Cause can also mean a motivation or an ideal or goal that a person or group is dedicated to. Cause has several other senses as a noun and one as a verb. In manner of speaking, the cause tells you why something happened. A cause is the spark that lights a fire. The cause of you being sick might be a bacteria or a virus that harms your body. You giving your niece a birthday present might be the cause of her being happy. The word cause is often used with the word effect, which means a resulting action that happens because of a cause.

• Real-life examples: Faulty wiring may be the cause of an electrical fire. John Wilkes Booth was the cause of Abraham Lincoln’s death (because Booth shot Lincoln). A giant iceberg was the cause of the sinking of the Titanic.
• Used in a sentence: Experts are still trying to figure out the cause of the mysterious plane crash. 

In this sense, cause is used as a verb to mean to bring about something.

• Used in a sentence: My late-night partying caused me to fail my exam.

Cause is also used as a synonym for motive or reason, meaning a person’s motivation for doing something. In this sense, cause is often used in law (usually as “just cause” or “sufficient cause”) to determine if someone had a valid reason for doing something.

• Used in a sentence: The lawyer argued that the company had fired his client without good cause.

A cause is something that a person or group believes in or an ideal or goal that they have dedicated themselves to.

• Real-life examples: Antiracism is a cause that wants to end racism. Environmentalism is a cause that wants to protect the environment from damage. If a friend of yours is very sick and you start a collection to help with medical bills, that too is a cause.
• Used in a sentence: I donated $50 to the cancer charity because they have a good cause.

Related Words

Cause, occasion refer to the starting of effects into motion. A cause is an agency, perhaps acting through a long time, or a long-standing situation, that produces an effect: The cause of the quarrel between the two men was jealousy. An occasion is an event that provides an opportunity for the effect to become evident, or perhaps promotes its becoming evident: The occasion was the fact that one man's wages were increased. See reason.

Other Word Forms

• causability noun
• causable adjective
• causeless adjective
• causelessly adverb
• causelessness noun
• causer noun
• noncausable adjective
• self-caused adjective
• subcause noun
• uncausable adjective
• undercause noun

Etymology

Origin of cause¹

First recorded in 1175–1225; Middle English, from Latin causa “case, reason, sake”

Origin of 'cause²

First recorded in 1400–50; late Middle English; aphetic variant

Explanation

A cause makes an effect, and you're likely to hear the phrase "cause and effect" when people are trying to analyze how things happen. Cause can also mean something worth fighting for — like social justice or animal rights. You might raise money for a good cause, like ending poverty. Once the doctor determines the cause of your illness, she might make it her personal cause to discover a cure. The verb cause is all about the action of producing an effect, like when you slice onions and it causes your eyes to water.

Example Sentences

The founding father’s hardheadedness could also sometimes cause trouble.

From Los Angeles Times • Apr. 12, 2026

For now, the biological cause of GLP-1 resistance remains unclear and is likely influenced by multiple factors.

From Science Daily • Apr. 12, 2026

Their estimates for how long prices would have to stay elevated to cause a recession vary from four to 55 weeks, with an average duration of 12 weeks.

From The Wall Street Journal • Apr. 12, 2026

The singer announced he was diagnosed with Ramsay Hunt syndrome, a shingles outbreak that can cause facial paralysis.

From Barron's • Apr. 12, 2026

How I wish I could just hold her hand for a moment, but I’ve been told to keep my distance as it could cause her harm to be seen with me.

From "Across So Many Seas" by Ruth Behar

Related Words

• element
• explanation
• matter
• motivation
• motive
• origin
• principle
• purpose
• root
• source