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

In most cases, agencies make reactive decisions based on visible failures and complaints rather than scientific deterioration trends. — Mark Pittman, Forbes.com, 25 June 2026

Everything about Shenzi, Banzai and Ed is giving Gemini energy — Shenzi is sharp, perceptive and strategic; Banzai is reactive and argumentative, while Ed contributes random and unpredictable laughter. — Valerie Mesa, PEOPLE, 24 June 2026

The plaintiffs allege Bio-Lab and the parent company, Kik LLC, had a history of chemical storage issues, and staff incorrectly tried to put out a water-reactive chemical reaction by adding water before the fire began, thereby causing the fire and toxic gas plume. — Irene Wright, USA Today, 23 June 2026

Like all La Roche-Posay products, this one is infused with the brand’s signature Thermal Spring Water, which provides soothing, anti-inflammatory benefits—a boon for aging skin, which becomes more reactive over time. — Jenny Berg, Glamour, 22 June 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