Oppenheimer

American  

[op-uhn-hahy-mer] / ˈɒp ənˌhaɪ mər /

noun

1. J(ulius) Robert, 1904–67, U.S. nuclear physicist.

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Oppenheimer British  

/ ˈɒpənˌhaɪmə /

noun

1. J ( ulius ) Robert. 1904–67, US nuclear physicist. He was director of the Los Alamos laboratory (1943–45), which produced the first atomic bomb. He opposed the development of the hydrogen bomb (1949) and in 1953 was alleged to be a security risk. He was later exonerated

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Oppenheimer Scientific  

/ ŏp′ən-hī′mər /

1. American physicist who directed the Los Alamos, New Mexico, laboratory during the development of the first atomic bomb (1942–1945). After World War II, he became an advocate for the peaceful use of atomic energy and opposed the development of the hydrogen bomb.

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Example Sentences

The Oppenheimer analysts said there was likely more room for McDonald’s to expand its beverage business through this year and next year.

From MarketWatch • Apr. 20, 2026

Mark Oppenheimer: Judy is the one who says that it’s not YA.

From Slate • Apr. 18, 2026

Christopher Nolan returns this year with his first film since 2023's Oppenheimer, which won the Oscar for best picture.

From BBC • Apr. 17, 2026

Oppenheimer analysts still believe in Nike’s turnaround but concede they are becoming “at least somewhat frustrated.”

From The Wall Street Journal • Apr. 10, 2026

That soured his first meeting with Oppenheimer, who was invited to the Oval Office on October 25, 1945, to discuss legislation for domestic control of the atom.

From "Big Science" by Michael Hiltzik