radio

1 of 4

adjective

ra·​dio ˈrā-dē-ˌō 

1

: of, relating to, or operated by radiant energy

2

: of or relating to electric currents or phenomena (such as electromagnetic radiation) of frequencies between about 3000 hertz and 300 gigahertz

3

a

: of, relating to, or used in radio or a radio set

b

: specializing in radio or associated with the radio industry

c(1)

: transmitted by radio

(2)

: making or participating in radio broadcasts

d

: controlled or directed by radio

radio

2 of 4

noun

plural radios

1

a

: the wireless transmission and reception of electric impulses or signals by means of electromagnetic waves

b

: the use of these waves for the wireless transmission of electric impulses into which sound is converted

2

: a radio message

3

: a radio receiving set

4

a

: a radio transmitting station

b

: a radio broadcasting organization

c

: the radio broadcasting industry

d

: communication by radio

radio

3 of 4

verb

radioed; radioing; radios

transitive verb

1

: to send or communicate by radio

2

: to send a radio message to

intransitive verb

: to send or communicate something by radio

radio-

4 of 4

combining form

see radi-

Examples of radio in a Sentence

Noun

The news was sent by radio.

I listen to the radio all the time.

I heard the news on the radio.

There's a problem with the car's radio.

The radio was playing very loudly.

The pilot's radio wasn't working.

Verb

The police radioed for backup.

The stranded sailors were radioing for help.

The pilot radioed in to the control tower.

The police radioed a report back to the station.

They radioed the Coast Guard for help.

Recent Examples on the Web

Adjective

Channel 4 told The Hollywood Reporter on Wednesday that an installment featuring the ex-radio host and also reportedly featuring singer Rag n Bone Man, JLS’ band member Aston Merrygold, broadcaster Edith Bowman, and comedian Jon Richardson, will no longer air as planned on April 18. —Lily Ford, HollywoodReporter, 8 Apr. 2026

The first night of two Apollo weekend shows presented by SiriusXM, featured the 36-year-old ripping off songs at a frantic pace — most with just a verse and chorus — satisfying day-one fans with fan-favorite, deep non-radio cuts as well as those only familiar with his No. 1 hits. —Gary Gerard Hamilton, Chicago Tribune, 22 Jan. 2023

Noun

Like fighter pilots, truck drivers sometimes adopt a handle, to identify themselves on CB radio. —Patrick Radden Keefe, New Yorker, 13 Apr. 2026

Not just the hits, though, as the channel also goes into deeper tracks not often played on the radio. —Richard Wagoner, Daily News, 13 Apr. 2026

Verb

For instance, just after Artemis 2 broke Apollo 13's distance record, Hansen radioed Mission Control asking for permission to name two heretofore anonymous craters on the moon — one after Integrity and one after Wiseman's late wife Carroll, who died of cancer in 2020. —Mike Wall, Space.com, 11 Apr. 2026

Reid Wiseman radioed Mission Control. —Noah Haggerty, Los Angeles Times, 11 Apr. 2026

Word History

Etymology

Noun and Adjective

short for radiotelegraphy

First Known Use

Adjective

1887, in the meaning defined at sense 1

Noun

1907, in the meaning defined at sense 1a

Verb

1919, in the meaning defined at transitive sense 1

Phrases Containing radio

• clock radio
• radio astronomy
• radio beacon
• radio car
• radio collar
• radio compass
• radio-controlled
• radio frequency
• radio galaxy
• radio range
• radio spectrum
• radio star
• radio-tag
• radio telescope
• radio-ulna
• radio wave
• shock radio/TV
• talk radio
• transistor radio

Rhymes for radio

• acknow
• aglow
• ago
• airglow
• aloe
• altho
• although
• ammo
• backflow
• backhoe
• banjo
• barbeau

Kids Definition

radio

1 of 4 noun

ra·​dio ˈrād-ē-ˌō 

plural radios

1

: the sending or receiving of signals using electromagnetic waves without a connecting wire

radio includes television and radar

especially : the use of these waves to carry sound that has been changed into electrical energy

2

: a radio receiving set

a transistor radio

3

: the radio broadcasting industry

radio

2 of 4 adjective

1

: of, relating to, or operated by radiant energy especially at radio frequencies

2

: of, relating to, or used in radio or a radio

radio commercials

radio

3 of 4 verb

: to communicate or send a message to by radio

radio-

4 of 4 combining form

1

: radiant energy : radiation

radioactive

2

: radioactive

radiocarbon

Etymology

Noun

a shortened form of radiotelegraphy, literally, "telegraphy by rays"; radio- from French radio- "radial, radiating," from Latin radius "ray, beam, spoke" — related to radiate, radius, ray entry 2

Combining form

derived from Latin radius "ray, beam, spoke"