activity

American  

[ak-tiv-i-tee] / ækˈtɪv ɪ ti /

noun

• activities
  plural

1. the state or quality of being active.

   There was not much activity in the stock market today. He doesn't have enough physical activity in his life.

2. a specific deed, action, function, or sphere of action.

   social activities.

3. work, especially in elementary grades at school, that involves direct experience by the student rather than textbook study.

4. energetic activity; animation; liveliness.

5. a use of energy or force; an active movement or operation.

6. normal mental or bodily power, function, or process.

7. Physical Chemistry. the capacity of a substance to react, corrected for the loss of reactivity due to the interaction of its constituents.

8. Physics.

   1. the number of atoms of a radioactive substance that disintegrate per unit of time, usually expressed in curies.

   2. radioactivity.

9. an organizational unit or the function it performs.

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activity British  

/ ækˈtɪvɪtɪ /

noun

1. the state or quality of being active

2. lively action or movement

3. any specific deed, action, pursuit, etc

   recreational activities

4. the number of disintegrations of a radioactive substance in a given unit of time, usually expressed in curies or disintegrations per second

5. 1. the capacity of a substance to undergo chemical change

   2. the effective concentration of a substance in a chemical system. The absolute activity of a substance B, λ B , is defined as exp (μ B RT ) where μ B is the chemical potential

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Other Word Forms

Derived Forms

• nonactivity
  noun
• preactivity
  noun
• superactivity
  noun

Inflected Forms

Nouns

• activities
  plural

Etymology

Origin of activity

First recorded in 1520–30; from Middle French or directly from Medieval Latin āctīvitās; see active, -ity

Explanation

An activity is something you do, or just the state of doing. You might plan some indoor activities for a rainy day, or you might just rely on watching your gerbils' activity in their cage. Usually, when you use an article like an or the in front of activity, you are referring to a specific event. For example, you might search for the best activity on the cruise ship to fill your afternoon — shuffleboard, anyone? If you take the article away, and you refer to activity, you are usually referring to action. If there is too much activity on the cruise ship dance floor, you might want to avoid that zone.

Example Sentences

See Examples For:

activity activities

In addition to Fed minutes, this week will also bring data on consumer sentiment and service-industry activity.

From Barron's ● Oct. 5, 2026

Researchers from Fujita Health University set out to investigate how quickly physical activity can influence gut motility in healthy adults.

From Science Daily ● Oct. 5, 2026

The main hall of Kyiv’s central train station buzzes with activity.

From The Wall Street Journal ● Oct. 4, 2026

Pitkanen said he was so far "fairly positive" about the project, as it will bring "large-scale business activity" and "life" to the rural municipality with a population of only around 8,800 people.

From Barron's ● Oct. 4, 2026

“My mom and older sister made these. I’m in charge of selling them. We’re raising money for the Elder care program. We want to get them stuff for arts and crafts and activity nights.”

From "Legendary Frybread Drive-In" by Cynthia Leitich Smith

Google, meanwhile, told AFP in an email that "tree felling activities have been taking place in compliance with Forestry Act requirements" and they "were awaiting further guidance from LVV on this matter."

From Barron's ● Oct. 4, 2026

Society chairman Philip Osman said a permanent observatory would encourage participation and also give the group the opportunity to organise community outreach activities.

From BBC ● Oct. 3, 2026

Normally when hacks happen, the evidence lies hidden behind corporate firewalls, but the swarms tracked by Piecha and others left traces of their activities scattered all over the internet—sometimes intentionally, to help each other.

From The Wall Street Journal ● Oct. 2, 2026

Healthy aging is about staying independent, maintaining mobility and continuing to enjoy everyday activities as you get older.

From Science Daily ● Oct. 2, 2026

Camp activities included séances, hymn singing, boating, archery, and picnics.

From "American Spirits" by Barb Rosenstock

Related Words

• act
• endeavor
• enterprise
• job
• project
• scheme
• task
• venture
• work