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

This would shift the system from a primarily reactive to a more predictive one. — Christopher McFadden, Interesting Engineering, 1 Nov. 2026

Executive Strategies For Implementation Applying TE to organizational settings requires a shift from reactive management to conscious engagement in leadership interactions. — Gia Tskhovrebadze, Forbes.com, 30 Oct. 2026

Meanwhile, researchers at Columbia University discovered that when microplastics and water mix, a third class of molecules, known as reactive oxygen species, is created. — Susanne Rust follow, Los Angeles Times, 29 Oct. 2026

To their credit, the creative minds behind the Absolute series don’t bother masking their politics — an especially bold move for anyone working in an industry with an often reactive and volatile fandom. — Christopher Cruz, Rolling Stone, 28 Oct. 2026

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

• active
• tractive
• attractive
• contractive
• extractive
• inactive
• proactive
• refractive
• subtractive
• 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