irradiate

verb

ir·​ra·​di·​ate i-ˈrā-dē-ˌāt 

irradiated; irradiating

transitive verb

1

a

: to affect or treat by radiant energy (such as heat)

specifically : to treat by irradiation

b

: to cast rays of light upon : illuminate

c

: to enlighten intellectually or spiritually

2

: to emit like rays of light : radiate

irradiating strength and comfort

intransitive verb

archaic : to emit rays : shine

irradiative

i-ˈrā-dē-ˌā-tiv 

adjective

irradiator

i-ˈrā-dē-ˌā-tər 

noun

Synonyms of irradiate

• illumine
• illuminate
• light

Examples of irradiate in a Sentence

The food was irradiated to kill any germs.

the light from a galaxy of flashing signs irradiates the heart and soul of Las Vegas

Recent Examples on the Web

His team added soil that had been irradiated almost five years earlier, and then closed the circuit. — Siddhant Pusdekar, Quanta Magazine, 1 June 2026

Boyd notes that the power in the beam matters but so does the material that is irradiated. — Deni Ellis Béchard, Scientific American, 13 Feb. 2026

Scientists irradiate male flies to sterilize them, then release them by the million. — Gretchen Wittenmyer-Stone, Fort Worth Star-Telegram, 16 June 2026

The sterile flies are irradiated and released en masse, designed to blanket a region experiencing an outbreak. — Evan Bush, NBC news, 7 June 2026

Word History

Etymology

Latin irradiatus, past participle of irradiare, from in- + radius ray

First Known Use

1603, in the meaning defined at transitive sense 1b

Rhymes for irradiate

• abdicate
• abrogate
• acetate
• activate
• actuate
• aggravate
• agitate
• alginate
• alienate
• allocate
• amputate
• angulate

Kids Definition

irradiate

verb

ir·​ra·​di·​ate ir-ˈād-ē-ˌāt 

irradiated; irradiating

1

a

: to cast rays of light on : illuminate

b

: to affect or treat by exposure to radiation (as of ultraviolet light, X-rays, or gamma rays)

2

: to give off like rays of light : radiate

irradiation

-ˌād-ē-ˈā-shən

noun

Medical Definition

irradiate

transitive verb

ir·​ra·​di·​ate ir-ˈād-ē-ˌāt 

irradiated; irradiating

: to affect or treat by radiant energy (as heat)

specifically : to treat by exposure to radiation (as ultraviolet light or gamma rays)