activity · noun /ækˈtɪv.ət̬.i/Full view
Nouns: activity, inactivity
Adjectives: active, inactive, interactive, proactive
Verbs: activate
Adverbs: actively
activity (EVENT)
A2 C usually plural something that is done for enjoyment, especially an organized event
Dictionary example:

The center offers a range of activities, such as basketball, swimming and tennis.

Learner example:

We did many activities: playing games, singing and [watching a] magic show. (Key English Test; A2; Thai)

activity (WORK)
B2 C or U the work of a group or organization to achieve an aim
Dictionary examples:

Energy companies have concentrated their business activity in Houston.

illegal/criminal activities

Learner example:

But Rollo was also a good man, so when a policeman, called Calloway, informed him about [Harry's] illegal activity, he turned against him. (First Certificate in English; B2; Italian)

activity (MOVEMENT)
B2 U when a lot of things are happening or people are moving around
Dictionary examples:

Officials are concerned by the low level of economic activity.

There was a lot of activity the other side of the room.

Learner example:

Technical progress and industrial activity are causing a lot of problems. (First Certificate in English; B2; Russian)

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