thermonuclear

adjective

ther·​mo·​nu·​cle·​ar ˌthər-mō-ˈnü-klē-ər 

-ˈnyü-,

nonstandard

-ˈn(y)ü-kyə-lər 

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

: of, utilizing, or relating to a thermonuclear bomb

thermonuclear war

a thermonuclear attack

Examples of thermonuclear in a Sentence

Hydrogen bombs are thermonuclear weapons.

Recent Examples on the Web

There’s some information about Atlanta on the tablet: Namely, that two thermonuclear weapons were there. —Kimberly Roots, TVLine, 18 Feb. 2025

The thermonuclear visit comes after Finance Minister Nirmala Sitharaman set aside $2.3 billion in the federal budget earlier this month to promote the development of nuclear power generation in India. —Ganesh Rao, CNBC, 13 Feb. 2025

This crucial detail is what boosts a weapon of mass destruction on the order of a few dozen kilotons to something like Castle Bravo, the first US thermonuclear bomb test. —Andrew Paul, Popular Science, 9 Jan. 2025

Modern thermonuclear weapons rely on what is called a plutonium pit. —Andrew Paul, Popular Science, 9 Jan. 2025

Word History

Etymology

International Scientific Vocabulary

First Known Use

1938, in the meaning defined at sense 1

Rhymes for thermonuclear

• antinuclear
• internuclear
• intranuclear
• mononuclear
• perinuclear
• polynuclear
• supranuclear
• binuclear
• nuclear
• polymorphonuclear

Kids Definition

thermonuclear

adjective

ther·​mo·​nu·​cle·​ar ˌthər-mō-ˈn(y)ü-klē-ər 

: of or relating to the transformations in the nucleus of atoms of low atomic weight (as hydrogen) that require a very high temperature (as in the hydrogen bomb or in the sun)

a thermonuclear reaction

a thermonuclear weapon