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

This plant is needed as the first Smolensk NPP reactor was built in 1982, and all three reactors are nearing the end of their operational permits. —Michael Gfoeller and David H. Rundell, Newsweek, 15 Jan. 2025

In recent months, Google, Microsoft and Amazon have each announced nuclear power deals, with Microsoft signing a deal with Constellation to bring the Three Mile Island reactor back online. —Cj Haddad, CNBC, 14 Jan. 2025

To convert heat from the reactor into electricity, the microreactor employs the open-air Brayton cycle, which is also used by jet engines and gas turbines. —IEEE Spectrum, 9 Jan. 2025

Existing reactors that are profitable would not be able to claim the credit. —Brad Plumer, New York Times, 3 Jan. 2025

Word History

First Known Use

1890, in the meaning defined at sense 1

Phrases Containing reactor

• atomic reactor
• hyper-reactor
• nuclear reactor

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)