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

Counter terrorism police said Hekmat Omar Ali Hakim, 49, of St James Road, Higher Broughton, Salford, had been charged with failing to disclose information regarding terrorist activity.

From BBC ● Aug. 20, 2026

Their gene activity was also more strongly focused on fundamental cell maintenance and protein production.

From Science Daily ● Aug. 20, 2026

He has filmed some of the activity on his phone.

From BBC ● Aug. 20, 2026

Cutting off Iran would also require Emirati authorities to crack down much more aggressively on opaque financial and trading activity, which could hurt Dubai’s role as a freewheeling global hub for commerce, capital and re-exports.

From The Wall Street Journal ● Aug. 19, 2026

It was an unusual activity, to be sure; but Clare, too, found that his greatest treasures were from the garbage.

From "The Undead Fox of Deadwood Forest" by Aubrey Hartman

He listed several activities that he said need to stop immediately: "oil smuggling, swap lines, cash transfers, exchange houses, ship registries, front companies."

From Barron's ● Aug. 20, 2026

The Tata family has long valued its ability to carry out a range of philanthropic activities through the Tata Trusts, funded largely by dividend income from Tata Sons.

From The Wall Street Journal ● Aug. 20, 2026

To combat the isolation and boredom, troops sometimes do fun activities aboard the ship, like hold singing competitions and picnics on the top deck.

From BBC ● Aug. 18, 2026

Forest Service chief Tom Schultz said it will allow for essential forest management activities, such as removing fire-prone dead timber.

From Los Angeles Times ● Aug. 18, 2026

What activities could you do with them to underscore the idea of the soundscape?

From "Music and the Child" by Natalie Sarrazin

Related Words

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