active

1 of 2

adjective

ac·​tive ˈak-tiv 

1

: characterized by action rather than by contemplation or speculation

an active life

2

: producing or involving action or movement

3

a

of a verb form or voice : asserting that the person or thing represented by the grammatical subject performs the action represented by the verb

Hits in "he hits the ball" is active.

b

: expressing action as distinct from mere existence or state

active verbs such as "eat" and "sing"

4

: quick in physical movement : lively

5

: marked by vigorous activity : busy

The stock market was active.

6

: requiring vigorous action or exertion

active sports

7

: having practical operation or results : effective

an active law

8

a

: disposed to action : energetic

took an active interest

b

: engaged in an action or activity

an active club member

c

of a volcano : currently erupting or likely to erupt compare dormant sense 2a, extinct entry 1 sense 1b

d

: characterized by emission of large amounts of electromagnetic energy

an active galactic nucleus

9

: engaged in full-time service especially in the armed forces

active duty

10

: marked by present operation, transaction, movement, or use

an active account

11

a

: capable of acting or reacting : reacting readily

active nitrogen

active ingredients

b

: tending to progress or to cause degeneration

active tuberculosis

c

of an electronic circuit element : capable of controlling voltages or currents

d(1)

: requiring the expenditure of energy

active calcium ion uptake

(2)

: functioning by the emission of radiant energy or sound

radar is an active sensor

12

: still eligible to win the pot in poker

13

: moving down the line : visiting in the set

—used of couples in contra dances or square dances

14

medical : producing active immunity

Active immunization against Bordetella pertussis, the causative agent of whooping cough, is now usually achieved with combined pertussis-tetanus-diphtheria (DTP) vaccine.

—Scientific American Medicine

actively adverb

activeness noun

active

2 of 2

noun

plural actives

: an active person : one engaged in an action or activity

fraternity alumni and actives

We announced in December that Instagram now has over 600 million monthly actives and recently passed 400 million daily actives.

—Mark Zuckerberg

Synonyms

Adjective

• alive
• functional
• functioning
• going
• live
• living
• on
• operating
• operational
• operative
• running
• working

Examples of active in a Sentence

Adjective

We stay active during the cold winter months by skiing and ice skating.

We are active members of our church.

While many give money to the organization, only a few are active participants.

She was politically active as a volunteer for her state representative.

They take an active interest in their children's education.

He has taken a more active role in the production of this album.

the bank's active and inactive accounts

Recent Examples on the Web

Adjective

Despite not having the silicone tips that fully block out noise, the pair of earbuds still demonstrates active noise cancellation. —Casey Clark, People.com, 2 Dec. 2024

This type of garlic preparation has more active antioxidants, which prevent cell damage, than fresh garlic.10 A 90-day clinical trial demonstrated that the people in the study who took the extract had less severe symptoms than those who didn't. —Nancy Lebrun, Verywell Health, 2 Dec. 2024

Noun

When to use vitamin C serum Like most actives, dermatologists recommend slowly incorporating vitamin C into your skin-care routine to avoid irritation. —Jennifer Hussein, Allure, 11 Dec. 2024

Even Serum All about biomimetic actives to mimic natural collagen and elastin in the skin to prevent the signs of aging, this serum delivers firmer-looking skin in just two weeks and reduces the appearance of dark spots in eight weeks, all while smoothing fine lines and wrinkles. —Celia Shatzman, Forbes, 26 Nov. 2024

Word History

Etymology

Adjective

Middle English, borrowed from Anglo-French & Latin; Anglo-French, borrowed from Latin āctīvus, from āctus (past participle of agere "to drive (cattle), cause to move, do") + -īvus -ive — more at agent

First Known Use

Adjective

14th century, in the meaning defined at sense 1

Noun

15th century, in the meaning defined above

Phrases Containing active

• active duty
• active immunity
• active-matrix
• active service
• active shooter
• active site
• active suspension
• active transport
• active vocabulary
• co-active
• optically active
• sexually active
• surface-active

Kids Definition

active

adjective

ac·​tive ˈak-tiv 

1

: producing or involving action or movement

2

: representing the subject as performing the action expressed by the verb

"hits" in "she hits the ball" is an active verb

3

: having or requiring quick or energetic movements

an active child

active sports

4

a

: ready for action

takes an active interest

b

: engaged or participating in an action or activity

an active member

c

: erupting or likely to erupt

an active volcano

5

: engaged in or requiring full-time service especially in the armed forces

active duty

6

: marked by present action or use

an active account

a student's active vocabulary

7

a

: capable of acting or reacting

active ingredients

b

: tending to progress or increase

active tuberculosis

actively adverb

activeness noun

Medical Definition

active

adjective

ac·​tive ˈak-tiv 

1

: capable of acting or reacting especially in some specific way

an active enzyme

active nitrogen

2

: tending to progress or to cause degeneration

active tuberculosis

3

: exhibiting optical activity

4

: requiring the expenditure of energy

active calcium ion uptake

5

: producing active immunity

active immunization

actively adverb

Legal Definition

active

adjective

ac·​tive

1

: characterized or accomplished by action or effort

active concealment

compare passive

2

: engaged or participating in action or activity

paying child support but not otherwise an active parent