adjective ther·mo·nu·cle·ar \ˌthər-mō-ˈnü-klē-ər, -ˈnyü-, ÷-ˈn(y)ü-kyə-lər\

Definition of thermonuclear

  1. 1 :  of, relating to, or employing transformations in the nuclei of atoms of low atomic weight (such as hydrogen) that require a very high temperature for their inception (as in the hydrogen bomb or in the sun) thermonuclear reaction thermonuclear weapon

  2. 2 :  of, utilizing, or relating to a thermonuclear bomb thermonuclear war a thermonuclear attack

Examples of thermonuclear in a sentence

  1. Hydrogen bombs are thermonuclear weapons.

Did You Know?

Nuclear is the adjective for nucleus, the main central part of an atom. The original nuclear explosives, detonated in 1945, were so-called fission bombs, since they relied on the fission, or splitting, of the nuclei of uranium atoms. But an even greater source of destructive power lay in nuclear fusion, the forcing together of atomic nuclei. The light and heat given off by stars such as the sun come from a sustained fusion--or thermonuclear--reaction deep within it. On earth, such thermonuclear reactions were used to develop the hydrogen bomb, a bomb based on a fusion reaction that merged hydrogen atoms to become helium atoms. The thermonuclear era, which began in 1952, produced bombs hundreds of times more powerful than those exploded at the end of World War II. Why the thermo- in thermonuclear? Because great heat is required to trigger the fusion process, and the trigger used is actually a fission bomb.

Origin and Etymology of thermonuclear

International Scientific Vocabulary

First Known Use: 1938

THERMONUCLEAR Defined for English Language Learners


adjective ther·mo·nu·cle·ar \ˌthər-mō-ˈnü-klē-ər, -ˈnyü-, ÷-ˈn(y)ü-kyə-lər\

Definition of thermonuclear for English Language Learners

  • : of or relating to the changes in the nucleus of atoms that happen at extremely high temperatures

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holding stubbornly to a belief or view

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