radio
radio — noun
1. a small machine, often kept in a kitchen or car, that picks up sound signals fro
a small machine, often kept in a kitchen or car, that picks up sound signals from the air so you can listen to music, news, and talk shows.
Ife keeps a small black radio on the windowsill above her kitchen sink.
countable: a/the radio as a physical object
The old car's radio crackled whenever Mateo drove through the mountain tunnel.
Greta turned on her bedside radio at six and listened to the morning weather report.
collocation: turn on / turn off the radio
Every shop along the beach had a cheap plastic radio playing reggae.
- portable radio
- car radio
- bedside radio
- switch on the radio
- transistor
old-fashioned word for a small portable radio
- wireless
older British word for the device, now dated
Grammar Patterns
a/the radio
on the radio
Usage Note
Refers to the physical equipment, not the content. Distinguish from sense 2 (the programmes themselves) and sense 4 (two-way communication equipment).
Common Mistakes
2. the shows, songs, and news that come out of a radio set; what you actually liste
the shows, songs, and news that come out of a radio set; what you actually listen to rather than the box itself.
Devika listens to the radio every evening while she cooks dinner for her parents.
fixed phrase: listen to the radio
I heard a brilliant interview with the chef Anong on the radio this morning.
collocation: on the radio (= broadcast on air)
Yusra heard the football final on the radio while painting the back fence.
fixed phrase: hear something on the radio
Christopher prefers the radio to television because he can do other things while listening.
- on the radio
- listen to the radio
- hear something on the radio
- airwaves
more journalistic; refers to broadcast content collectively
Grammar Patterns
on the radio
listen to the radio
Usage Note
Almost always uncountable and used with 'the'. The phrase 'on the radio' marks this sense — never 'in the radio'. Distinct from sense 1 (the appliance) and sense 3 (the industry).
Common Mistakes
3. the business and activity of making and sending out spoken and musical shows for
the business and activity of making and sending out spoken and musical shows for the public, treated as a whole field of work.
Beatrix has worked in radio for twenty years, mostly as a news producer in Vienna.
collocation: work in radio (industry sense)
After leaving television, Ryo moved into radio and now hosts a popular jazz show.
pattern: move into radio (= enter the industry)
Local radio is struggling to keep listeners as more young people stream music online.
The university offers a degree in radio and podcast production.
- work in radio
- career in radio
- local radio
- commercial radio
- broadcasting
wider term; also covers television
- television
the parallel visual broadcasting industry
Grammar Patterns
work in radio
in/on radio
Usage Note
Uncountable and usually appears without an article: 'work in radio', 'a career in radio'. Refers to the field as a whole, distinct from the content (sense 2) or one specific station.
Common Mistakes
4. a handheld or built-in device used by pilots, sailors, police, and rescue teams
a handheld or built-in device used by pilots, sailors, police, and rescue teams to talk to each other across distance, or the spoken messages they send through it.
The pilot, Élise, asked the tower for landing permission over her cockpit radio.
collocation: over the radio (= via two-way device)
Each firefighter on the crew carries a small radio clipped to the shoulder strap.
We received a radio from the lost climbing party at four in the morning.
uncountable use: 'a radio' = a transmitted message
The captain ordered the crew to report any fishing boats by radio every half hour.
collocation: by radio (= using two-way equipment)
- over the radio
- by radio
- two-way radio
- ship's radio
- police radio
- walkie-talkie
informal; specifically a small handheld two-way radio
- transceiver
technical term for a combined transmit-receive device
Grammar Patterns
over the radio
by radio
Usage Note
Subject is typically aircrew, ship crew, emergency services, or military. Distinguish from sense 1: a kitchen radio only receives broadcasts; this device sends and receives. The phrase 'over the radio' in this sense means via the two-way handset, not via a broadcast channel.
Common Mistakes
radio — verb
1. to use a two-way radio to speak to someone at a distance, especially to ask for
to use a two-way radio to speak to someone at a distance, especially to ask for help or pass on important news from a ship, plane, or remote spot.
When the engine failed, Mateo radioed the coastguard and gave their exact position.
pattern: radio + person (transitive)
The mountain guide radioed for help after Zayd slipped on the icy ridge.
fixed phrase: radio for help
Officer Sayaka radioed that she had spotted the missing child near the river.
pattern: radio + that-clause
The pilot radioed ahead to warn the airport of a small fire in the cargo hold.
collocation: radio ahead (= warn in advance)
- radio for help
- radio the base
- radio ahead
- radio in a position
Grammar Patterns
radio someone
radio for help
radio that + clause
Usage Note
Subject is almost always someone with professional radio equipment (pilot, captain, officer, ranger). Often appears in emergency or urgent contexts. The verb takes either a person ('radio the base'), a purpose ('radio for backup'), or a clause ('radio that the road is blocked').
Common Mistakes
radio — adjective
1. powered by, or having to do with, the kind of invisible energy that travels thro
powered by, or having to do with, the kind of invisible energy that travels through space as waves, used in scientific writing about heat, light, and similar effects.
Hot stars shine as visible light, but cool gas clouds glow mainly in the radio part of the spectrum.
contrast with visible light: radio part of the spectrum
Karl Jansky showed in 1933 that the centre of our galaxy emits faint radio energy as well as ordinary light.
named discovery: emits radio energy alongside visible light
Professor Ravindra published a paper on radio phenomena in distant nebulae.
The detector responds to radio energy from the surface of the sample.
- radio energy
- radio phenomena
- radio part of the spectrum
- radiant
the modern everyday equivalent in physics writing
Grammar Patterns
radio + technical noun
Usage Note
Almost only seen in older or specialised physics texts. A modern reader would more often meet 'radiant' or 'radiative'. Distinct from sense 2, which fixes the meaning to a precise frequency band.
2. describing electrical signals or waves whose frequency falls in the band roughly
describing electrical signals or waves whose frequency falls in the band roughly between three kilohertz and three hundred gigahertz, the band used for wireless communication.
Mobile phones, Wi-Fi, and television all share parts of the radio spectrum.
fixed term: radio spectrum
The new antenna can pick up radio waves from very deep in space.
fixed term: radio waves
Engineer Beatrix designed a filter that blocks unwanted radio frequencies above one gigahertz.
fixed term: radio frequencies
Hospitals limit radio emissions near the MRI room to avoid blurry scans.
- radio waves
- radio frequency
- radio spectrum
- radio signals
- RF
the everyday engineering abbreviation, especially in 'RF signal'
Grammar Patterns
radio + frequency / waves / spectrum
Usage Note
Almost always attributive in fixed technical compounds: 'radio waves', 'radio frequency', 'radio spectrum'. Distinguish from sense 1 (broader 'radiant energy' meaning) and sense 3 (about the receiver as an object).
3. describing the parts, accessories, or repairs that belong to a radio set itself
describing the parts, accessories, or repairs that belong to a radio set itself — for example its dial, antenna, or speaker.
Christopher repaired the broken radio dial on his grandfather's vintage set.
compound: radio dial (part of a set)
The shop on Market Street sells second-hand radio parts at very low prices.
compound: radio parts
Mira clipped the radio antenna back into place after the storm.
An old radio cabinet stood in the corner of the museum's living-room display.
- radio dial
- radio antenna
- radio parts
- radio repair
Grammar Patterns
radio + part of a set
Usage Note
Used in everyday compound nouns naming pieces of the device: radio dial, radio antenna, radio cabinet, radio repair. Distinct from sense 4, which describes work or careers in the broadcasting industry.
4. describing a person, job, or company whose main work is making radio shows — for
describing a person, job, or company whose main work is making radio shows — for example a presenter, a station, or a producer.
Isabela became a famous radio presenter after winning a young-broadcasters' competition in São Paulo.
compound: radio presenter (industry role)
The radio station near our school plays mostly hip-hop and Latin pop.
compound: radio station
Ryo's first radio job paid almost nothing, but he learned to edit interviews quickly.
The country has only three independent radio companies left after last year's mergers.
- radio presenter
- radio host
- radio station
- radio journalist
- broadcasting
wider; covers television too
Grammar Patterns
radio + person/role/company
Usage Note
Subject of the modified noun is typically a human role (presenter, host, journalist) or a business (station, network, company). Distinct from sense 3, which describes physical parts of a set, and sense 6, which focuses on the activity of broadcasting itself.
5. describing a message, signal, or piece of news that has been carried over the ai
describing a message, signal, or piece of news that has been carried over the air by radio waves rather than by wire or post.
The captain woke up to a sudden radio message warning of bad weather to the north.
compound: radio message (transmitted content)
Every hour, the lighthouse sends out a short radio signal to passing ships.
compound: radio signal
Ife received a confused radio report about strange lights over the airport.
The astronauts heard the prime minister's words through a fuzzy radio link.
- radio message
- radio signal
- radio broadcast
- radio link
- radio report
- broadcast
as adjective, focuses on one-to-many transmission
Grammar Patterns
radio + signal/message/broadcast
Usage Note
Modifies abstract things being carried (message, signal, report, broadcast, link), not the equipment or the people. Compare with sense 7, which describes things being controlled remotely rather than just sent.
6. describing an event or piece of work that happens live on the radio — for exampl
describing an event or piece of work that happens live on the radio — for example an interview, a debate, or a fund-raising drive carried out on air.
The mayor agreed to a thirty-minute radio debate the night before the local election.
compound: radio debate (on-air event)
Anong's first radio appearance was on a Sunday morning gardening show.
compound: radio appearance
The charity ran a five-hour radio appeal and raised enough for a new ambulance.
compound: radio appeal
Devika's school organised a small radio play to celebrate the end of term.
- radio debate
- radio interview
- radio appearance
- radio play
- radio appeal
Grammar Patterns
radio + activity/event noun
Usage Note
Modifies activity nouns (debate, appearance, appeal, play, performance), unlike sense 4, which modifies job titles or companies, and sense 5, which modifies the message being sent.
7. describing toys, drones, or machines that one person guides from a distance by p
describing toys, drones, or machines that one person guides from a distance by pressing buttons on a small handset that sends signals through the air.
For his birthday, Zayd received a tiny radio-controlled helicopter that flew up to the ceiling.
fixed compound: radio-controlled helicopter
The model boat club meets every Saturday to race radio-controlled yachts on the lake.
Engineers used a radio-controlled robot to inspect the damaged reactor from a safe distance.
Mira's son spent the whole afternoon driving his red radio-controlled car around the garden.
fixed compound: radio-controlled car
- radio-controlled car
- radio-controlled aircraft
- radio-controlled drone
- radio-controlled robot
- remote-controlled
more general; covers infrared and Bluetooth too, not only radio
Grammar Patterns
radio-controlled + vehicle/device
Usage Note
Almost always written with a hyphen as 'radio-controlled' before the noun. The thing modified is a moving toy, drone, vehicle, or robot — not a message (sense 5) or an event (sense 6). The everyday short form is 'RC' (e.g. 'an RC car').
Common Mistakes
Word family
- radioactiveadjectiveB2
- radioactivitynounB2
- radiologynounC1
- radiologistnounC1
- radiateverbC1
- radiationnounB2
Synonym discussion
Sense: noun/1
All four words name household devices that produce sound, but they refer to different things and overlap only loosely. A radio is the receiver itself — it picks up broadcast signals from the air and turns them into sound, so a small kitchen radio is the basic example. A stereo is bigger and more about playing your own music: it usually combines an amplifier, two or more speakers, and inputs for CDs, vinyl, or streaming, and it may include a radio inside but is not centred on broadcasts. A speaker on its own makes no sound until something feeds it audio, so it is a part rather than a complete device. Transistor is an old-fashioned word for a small portable radio, especially the pocket-sized models popular in the 1960s; today it sounds dated. Quick test: 'I'll switch on the radio for the news' (radio); 'I bought a new stereo for my flat' (stereo); 'plug the speaker into your phone' (speaker).
Common collocations
Nouns
- radio station
- radio show
- radio host
- radio signal
- radio wave
- radio broadcast
Adverbs
Phrases
- turn on the radio
- turn off the radio
- listen to the radio
- tune the radio
- work in radio
Prepositions
- on the radio
- over the radio
- by radio
- via radio
Etymology
The word entered English at the very end of the nineteenth century, shortened from 'radiotelegraphy' — the new science of sending messages without wires by means of waves that radiate outward. The first part of that long word comes from Latin 'radius', meaning a ray or a spoke, the same image as a beam shooting out from a centre. By the 1910s, ships were sending 'radio' messages across the ocean; by the 1920s, the same name had transferred to the new home device that picked up public broadcasts, and from there to the broadcasts themselves and finally to the whole industry.