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

Because this type of multipoint investigation is reactive, the product that’s suspected of causing the illness may have already moved through the supply chain into stores or restaurants and has already been consumed. — Karen Garcia, Los Angeles Times, 24 July 2026

Personally, niacinamide has held a regular place in my routine for years to treat my oil-prone, reactive skin. — Jenny Berg, Vogue, 23 July 2026

Nation-state actors, ransomware groups and supply chain infiltrators now operate with a patience and precision that reactive tools were never built to match. — Kumar Ritesh, Forbes.com, 22 July 2026

Free radicals are highly reactive molecules that damage DNA, cells, and tissues. — Lana Barhum, Verywell Health, 22 July 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