reactor

noun

re·​ac·​tor rē-ˈak-tər 

1

: one that reacts

2

: a device (such as a coil, winding, or conductor of small resistance) used to introduce reactance into an alternating-current circuit

3

a

: a vat for an industrial chemical reaction

b

: a device for the controlled release of nuclear energy (as for producing heat)

Examples of reactor in a Sentence

Recent Examples on the Web

Although the reactor was not considered an active part of Iran's nuclear program, its destruction means Iran will likely never be able to complete it. —Geoff Brumfiel, NPR, 26 June 2025

After diplomacy with France and the United States failed to persuade the two countries to halt construction of the reactor, Prime Minister Menachem Begin concluded that attacking the reactor was Israel’s best option. —Jeffrey Fields, The Conversation, 24 June 2025

Nuclear energy is pushed even further out: The U.S. Department of Energy’s Pathways to Commercial Liftoff report notes that broad deployment of next-generation reactors is unlikely to begin before 2035. —Chris Hopper, Fortune, 24 June 2025

That's what the Commonwealth Scientific and Industrial Research Organization (CSIRO) in Australia is hoping to accomplish with its latest breakthrough, the beam-down solar reactor. —Abhimanyu Ghoshal, New Atlas, 23 June 2025

Word History

First Known Use

1890, in the meaning defined at sense 1

Phrases Containing reactor

• atomic reactor
• hyper-reactor
• nuclear reactor

Rhymes for reactor

• attractor
• cofactor
• compactor
• contactor
• contractor
• distractor
• extractor
• impactor
• protractor
• redactor
• refractor
• retractor

Kids Definition

reactor

noun

re·​ac·​tor rē-ˈak-tər 

1

: one that reacts

2

: a device for the controlled release of nuclear energy (as for producing heat)

Medical Definition

reactor

noun

re·​ac·​tor rē-ˈak-tər 

1

: one that reacts: as

a

: a chemical reagent

b

: an individual reacting to a stimulus

c

: an individual reacting positively to a foreign substance (as in a test for disease)

reactors to tuberculin

2

a

: a piece of equipment in which a chemical reaction and especially an industrial chemical reaction is carried out

b

: a device for the controlled release of nuclear energy (as for producing heat)