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

The antioxidants in quinoa fight oxidative stress (an imbalance between antioxidants and highly reactive free radical molecules), which causes tissue damage and raises the risk of chronic health conditions. —Carrie Madormo, Health, 3 Mar. 2026

These advancements allow research teams to move from reactive analysis to proactive insight generation. —Ascend Agency, Mercury News, 3 Mar. 2026

But one way to see Trump is as a basically reactive figure. —Ben Smith, semafor.com, 2 Mar. 2026

Women who are anxious, overwhelmed, or emotionally reactive get labeled as depressed or hormonal. —Sarah Oreck, SELF, 2 Mar. 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

• 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