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ground zero

noun

Definition of ground zero

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 2a

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

3 :the very beginning :square one

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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

First Known Use of ground zero

1946

ground zero Synonyms

Synonyms

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

Related Words

headquarters; happy hunting ground, hive, hotbed, hot spot, playground, playland; kernel, nub, pith; deep, thick; essence, quintessence, soul; attraction, lodestone (also loadstone), magnet, polestar

GROUND ZERO Defined for English Language Learners

ground zero

noun

Definition of ground zero for English Language Learners

: the point on the earth's surface directly above, below, or at which an explosion (especially a nuclear explosion) occurs
: the central point in an area of fast change or intense activity
: the beginning state or starting point

Learn More about ground zero

Thesaurus: All synonyms and antonyms for ground zero Britannica.com: Encyclopedia article about ground zero

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Examples: ground zero in a Sentence