I used to wonder why people called a radio set a “wireless” (mind you, I don’t think I’ve heard the expression “radio set” in a while). That was before I found myself involved with writing dictionaries. I soon discovered that radios were “wireless” not because they lacked a power cable, but because the radio waves were being transmitted through the air, by radio telegraphy, rather than along wires.

I’m fascinated by how change comes about, in society, and in language. So it was lucky that I ended up working on the Oxford English Dictionary, eventually becoming the dictionary’s chief editor for 20 years. The OED and the BBC have in many ways followed similar paths, opening up access in ways that didn’t seem possible when I started out as a trainee lexicographer in the mid-1970s. One of the things I quickly discovered was that words are an index to the changes in the world around us: any new technology, any political crisis – even any shift of social perspective – brings with it new vocabulary, and of course more work for lexicographers.

One of my first memories of the dictionary was of the editor, Robert Burchfield, talking about a booklet he’d been asked to compile for the BBC (or the B.B.C., as it then was). Called The Spoken Word, it offered advice to broadcasters on their use of English. He covered punctuation, grammar, and vocabulary – he warned that acoustic should be pronounced “ac-oo-stic” not “ac-ow-stic” (as people used to) and that adult should be accented on the first syllable. Or chaos would ensue… For the dictionary, as for the Corporation, the 1970s marked the end of the era of Reithian certainty, when education and culture – or at least what was then regarded as education and culture – were prioritised. Listeners and viewers were emerging from the days of “warming up” the set, watching the test card (I knew people who did) and rotating the tuner to find a station. In keeping with its etymology (Greek tele- and Latin vision: seeing at a distance), the role of television in its early days was to bring into the home images and sounds from far away: a coronation, an orchestral performance, a newsreader sitting in a studio in London. You were grateful to Auntie Beeb for presenting you with these wonders. BBC Sport granted you a Grandstand view, while Robert Robinson politely solicited your Points of View.

User engagement” (a term to which I have never properly acclimatised myself) came slowly both to the Beeb and to dictionaries. As children in the 60s we were encouraged to “request” disc jockeys to play records on “request shows”. Nowadays, we are more likely to text or tweet for a “shout-out”.

The television set itself was the box from 1950, the telly from 1954, the idiot box from the 1955, the tube (now dimly remembered via YouTube, whose original slogan was Broadcast Yourself) and from 1959, the gogglebox (now revived ironically on the Channel 4 show).

Language is a powerful tool, and broadcasting authorities recognised this. Building up a public lexicon of broadcasting was a way of ensuring that people would feel engaged. The word broadcasting itself is a good case in point. It literally means scattering seeds by hand in a field. By the 1920s, it was becoming the standard term for the dissemination of information by radio and TV transmitters. The United States coined newscasting and narrowcasting (the latter, transmissions aimed at a particular audience such as children or sports enthusiasts) in the 1930s.

Think about “audience”. It’s a passive word: we broadcast, you listen or watch. But by the 1970s, audiences were fighting back. The BBC had already changed the “Light Programme” to Radio 2, the intellectual “Third Programme” to Radio 3 and the “Home Service” (created following the outbreak of the Second World War in 1939, at a time when “home service” meant military service at home, rather than abroad) to Radio 4 in 1967. As society opened up even more, we didn’t just want television when the broadcasters decided, we wanted it on all the time.

If breakfast television was a breakthrough in the early 1980s, then things changed seismically with the launch of reality TV. The expression can be traced back to the United States in the 1960s and 70s, but hit our screens with a jolt in the late 1990s and early 2000s. Viewers could feel that they were having a real say, even control, as everyday scenes and emotions (or – increasingly – extreme versions of these) were put under the microscope in the Big Brother house or in the jungle and audiences voted on who should leave or stay.

The old certainties of soap opera and sitcom were in danger. Could they reinvent themselves, too? The expression soap opera dates from the late 1930s in the United States (again): so called because some of the early sponsors/advertisers were detergent (or “soap”) manufacturers. Situation comedy also came to us from the States in the 1950s, popularised by I Love Lucy. It pretty soon became sitcom (which in turn spawned the cinema term romcom in the early 70s).

It can seem as if in the 21st century, the viewers have stormed the Reithian citadel. But who are the masters? Are the TV companies still in control? If not, how come reality has turned into celebrity? We have embraced that, too, as the A-list parades became an essential complement to the Ordinary Joe versions of Strictly, Bake Off and Celebrity Mastermind.

These are massive changes, as television has tried to keep pace with changes in society, still educating as well as entertaining. Documentaries have spawned mockumentaries and rockumentaries, broadcasting has led to podcasts, the past is kept alive by repeats, replays (do we still say action replays?) and iPlayer: even wireless has made a comeback. And yet we still have Points of View, Panorama and Doctor Who, from the days of my earliest encounters with television. These days you can turn on, you don’t need to tune in, and if you drop out, you can come back later and see it on plus one.