ground zero

noun

1

: the point directly above, below, or at which an explosion and especially a nuclear explosion occurs

2

: the center or origin of rapid, intense, or violent activity or change

Mingo Junction … sits at ground zero of the longest steelworker strike in American history.

—Michael Janofsky

broadly : center sense 2a

… the party town that served as ground zero for those corporate … bashes.

—Rich Eisen

3

: the very beginning : square one

We'll have to go back to ground zero and start over.

Synonyms of ground zero

• center
• capital
• hub
• mecca
• focus
• base
• nucleus
• core
• seat
• nerve center
• heart

Examples of ground zero in a Sentence

ground zero in the battle over immigration laws

a city that was once ground zero for the insurance industry

Recent Examples on the Web

Florida is often called ground zero for climate impacts. —Yoca Arditi-Rocha, The Orlando Sentinel, 20 Feb. 2026

And Marin County is ground zero for the Grateful Dead. —Shirley Halperin, Rolling Stone, 17 Feb. 2026

California, and specifically the Bay Area, was ground zero for the craft beer movement with pioneering breweries like Anchor Brewing, New Albion, Triple Rock, Buffalo Bill’s, Sierra Nevada, Pete’s Wicked Ales, Lagunitas and Russian River. —Jay R. Brooks, Mercury News, 16 Feb. 2026

Some local governments are already on the case – and Atlanta is ground zero. —Bloomberg, Oc Register, 10 Feb. 2026

Word History

First Known Use

1946, in the meaning defined at sense 1

Rhymes for ground zero

• nonzero
• subzero
• biro
• spiro
• superhero

Kids Definition

ground zero

noun

1

: the site of a nuclear explosion

2

: the center of rapid, intense, or violent activity or change

3

: the very beginning : square one