ground zero

noun

1

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

2

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

broadly : center sense 2a

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

—Rich Eisen

3

: the very beginning : square one

Synonyms

• axis
• base
• capital
• center
• central
• core
• cynosure
• epicenter
• eye
• focus
• heart
• hub
• locus
• mecca
• navel
• nerve center
• nexus
• nucleus
• omphalos
• seat

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

Higher education | School shooters California Democrats open special session to Trump-proof state priorities DACA recipients worry their protection from deportation won’t last another Trump term A California federal court was ground zero for hashing out Trump’s border policies. —Paul Krugman, The Mercury News, 29 Nov. 2024

As the news headlines show, Greenland’s ice sheet is ground zero of earth’s shifting climate. —Stephanie Vermillion, Outside Online, 21 Nov. 2024

Meanwhile, maritime crews put themselves in harm’s way over and over, pointing their bows back toward ground zero to pick up still more passengers desperate to escape Manhattan Island. —Jessica Dulong, CNN, 11 Sep. 2024

One affable engineer recalls being summoned to ground zero on a Sunday. —Karl Vick, TIME, 11 Sep. 2024

Word History

First Known Use

1946, in the meaning defined at sense 1

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