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

Their decision-making tends to be reactive, risk-averse and focused on short-term survival rather than long-term success. —Cheryl Robinson, Forbes, 28 Feb. 2025

Brown-rot fungi leave the lignin largely intact but release highly reactive molecules that break down the cellulose, leaving behind a brown, crumbly substrate. —Katarina Zimmer, Smithsonian Magazine, 28 Feb. 2025

Best Practical Explosion Awarded to any sequence that involves any reactive substance that amounts to an explosion. —Roxana Hadadi, Vulture, 27 Feb. 2025

Both metals are among the least reactive in the periodic table and have a variety of uses in different fields, including aesthetic and scientific applications. —Victor Rosario, Sacramento Bee, 26 Feb. 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