reactive

adjective

re·​ac·​tive rē-ˈak-tiv 

1

: of, relating to, or marked by reaction or reactance

2

a

: readily responsive to a stimulus

b

: occurring as a result of stress or emotional upset

reactive depression

reactively adverb

reactiveness noun

Examples of reactive in a Sentence

The government's response to the problem was reactive rather than proactive.

Recent Examples on the Web

Organizations that move from reactive to proactive SaaS security tend to see their average incident response times drop. —Amir Khayat, Forbes.com, 5 Aug. 2025

Residents can safely dispose of products containing corrosive, toxic, ignitable or reactive substances. —Post-Tribune, Chicago Tribune, 4 Aug. 2025

This, in turn, can produce reactive oxygen species (ROS)—harmful molecules that have the ability to damage both cellular membranes and DNA. —Ian Randall, MSNBC Newsweek, 4 Aug. 2025

Milder ingredients include tea tree oil or green tea, which also provide skin-soothing benefits (essential for reactive, acne-prone skin). —Lily Wohlner, Allure, 30 July 2025

Word History

First Known Use

1717, in the meaning defined at sense 1

Phrases Containing reactive

• C-reactive protein
• hyper-reactive
• reactive arthritis

Rhymes for reactive

• attractive
• contractive
• extractive
• inactive
• proactive
• refractive
• subtractive
• active
• tractive
• bioactive
• hyperactive
• interactive

Kids Definition

reactive

adjective

re·​ac·​tive rē-ˈak-tiv 

1

: of or relating to reaction

2

: reacting or tending to react

reactively adverb

reactiveness noun

reactivity

(ˌ)rē-ˌak-ˈtiv-ət-ē 

noun

Medical Definition

reactive

adjective

re·​ac·​tive rē-ˈak-tiv 

1

a

: of, relating to, or marked by reaction

reactive symptoms

a reactive process

b

: capable of reacting chemically

highly reactive materials

2

a

: readily responsive to a stimulus

the skin of the geriatric is less reactive than that of younger persons

—Louis Tuft

b

: occurring as a result of stress or emotional upset especially from factors outside the organism

reactive depression