atomic bomb

American  

[uh-tom-ik bom] / əˈtɒm ɪk ˌbɒm /

Also atom bomb

noun

1. a bomb whose potency is derived from nuclear fission of atoms of fissionable material with the consequent conversion of part of their mass into energy.

2. a bomb whose explosive force comes from a chain reaction based on nuclear fission in U-235 or plutonium.

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atomic bomb British  

noun

1. Also called: A-bomb.   fission bomb.  a type of bomb in which the energy is provided by nuclear fission. Uranium-235 and plutonium-239 are the isotopes most commonly used in atomic bombs Compare fusion bomb

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atomic bomb Scientific  

1. A very destructive bomb that derives its explosive power from the fission of atomic nuclei. Atomic bombs usually have plutonium 239 or uranium 235 as their fissionable material.

2. Also called atom bomb

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atomic bomb ¹ Cultural  

1. A bomb that is powered by nuclear fission, and therefore produces a quick release of energy and great destruction.

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atomic bomb ² Cultural  

1. A nuclear weapon whose enormous explosive power results from the sudden release of energy from a fission reaction. (See also Hiroshima (see also Hiroshima), hydrogen bomb, Nagasaki, and Strategic Arms Limitation Talks [SALT].)

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Etymology

Origin of atomic bomb

First recorded in 1910–15

Compare meaning

How does atomic-bomb compare to similar and commonly confused words? Explore the most common comparisons:

• hydrogen bomb vs. atomic bomb
• hydrogen vs. atomic bomb

Example Sentences

The Wende Museum in Culver City opened its doors in 2017 inside a former 1949 atomic bomb shelter.

From Los Angeles Times • May 10, 2026

Iran denies seeking a nuclear weapon and the UN nuclear watchdog says that an atomic bomb was not imminent before the war.

From Barron's • Apr. 23, 2026

One of them in Nagasaki survived the 1945 atomic bomb blast and is still in working order, 117 years after it was fabricated and shipped from Scotland.

From BBC • Feb. 16, 2026

“The Most Awful Responsibility” sympathetically portrays Truman’s conflicted soul over the mass death inflicted by the atomic bomb.

From The Wall Street Journal • Jan. 16, 2026

During the war she’d earned legendary status in the Soviet spy service by sneaking past FBI agents with atomic bomb plans hidden in a tissue box.

From "Fallout: Spies, Superbombs, and the Ultimate Cold War Showdown" by Steve Sheinkin

Related Words

• atom bomb
• hydrogen bomb
• neutron bomb
• nuclear warhead