What’s in a name? Quite a lot, if you’re the Doctor, or Basil, or Theta Sigma, or δ³Σx², or whatever Doctor Who's lead character is really called.


It’s probably not Basil, if we’re honest. But that’s the name he gives in 2017's The Zygon Inversion, and the Doctor never lies, right? Apart from when the Doctor does lie, which is all the time.

But if not Basil, or 'Doctor Who,' then what?

What is the Doctor's real name?

What is very clear is that the Doctor doesn’t want us to know, actually. When he first met River Song, David Tennant's Tenth Doctor was shocked and horrified that she knew his name, stating there was “only one reason” he would ever divulge that information. (We suspect that reason was marriage, because it was during their wedding ceremony, now in his Eleventh incarnation, that he supposedly whispered it in her ear – on the other hand, he could equally have been saying "Don't worry, I'm actually a robot version of me with the tiny real me hiding inside." Time Lord weddings are complicated).

Around the same time, the witch (sorry, Carrionite) Lilith claimed the Doctor was hiding his true name from her “in despair”, while psychic Roman teenager Evelina said his “true name” was “hidden” even from her. Intriguing.

During his next incarnation, keeping his name out of the headlines was virtually a full-time job: according to Dorium Maldovar, the riddle ‘Doctor Who?’ was “The question that must never be answered”. The Great Intelligence was desperate to get its hands on the information (in so much as a formless entity can get its hands on anything), while, on the opposite side, The Silence was an entire religion/spooky monster club founded on stopping the Doctor from ever blabbing it.

In Eleven’s dying moments, we learned that the Doctor’s real name was the signal chosen by the Time Lords to return to our universe – kicking off a massive galactic bunfight in the process – until Clara persuaded them that the only name that really mattered was ‘the Doctor’.

Quite right, too.

Clara herself had briefly learned the Doctor’s real name in a book, The History of the Time War (not available in any good high street bookshops, sadly) but some timey-wimey business left her with no memory of it. D’oh!

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Now, following the events of The Timeless Children for Jodie Whittaker's Doctor, we can't be sure that even the Doctor is aware of his/her real birthname...could this be any more confusing?

Anyway, with total disrespect to our hero’s wishes – and the possible safety of the universe – let’s have a look at some theories of what the Doctor might be called…

The Doctor's name is... The Doctor

Firstly, we need to ask if the Doctor might actually be the Doctor's real name. Who knows, it might be as common as Steve or Kevin on Gallifrey?

But the evidence would suggest not. In The Name of the Doctor, Matt Smith’s Time Lord told Clara he had chosen the name ‘the Doctor’ as a promise – a promise never to be cruel or cowardly; to never give up, and never give in. Famously, he refused to use the title during the Time War, feeling his actions didn’t live up to the promise.

The Valeyard – a sort of Hyde to the Doctor’s Jekyll, distilled from the dark side of his/her personality – also stated the name is an alias, while John Simm's Master mocked him for styling himself as “the man who makes people better”.

As usual, though, the Master got it a bit wrong as, according to River Song, the opposite is actually true: we get the word Doctor from him: “the word for healer and wise man throughout the universe”, based on tales of the Doctor’s legendary exploits. (An idea, as RadioTimes.com reported, that Steven Moffat first idly proposed in an internet chatroom 20 years ago.)

Incidentally, the Doctor does appear to possess several actual doctorates, including, according to 2011’s The God Complex, one for cheese-making. But that might have been a joke.

The Doctor's name is... John Smith

The Doctor’s most common alias (apart from the Doctor, obviously), this is his standard pseudonym on Earth. Jon Pertwee’s Doctor used it all the time while stranded here in the 70s (or was it the 80s?) and he’s still rocking it today, including when the Twelfth Doctor did 'deep cover' as Coal Hill School’s caretaker. He even became John Smith, for real, when he turned human to hide from The Family of Blood. Oh, and it’s written on his library card, which is probably, like, totally illegal, right?

The Doctor's name is... Theta Sigma

Theta Sigma – or ΘΣ, if you’re feeling flash – was the nickname given to the Doctor at the Time Lord Academy on Gallifrey, according to Drax, a student contemporary from “the class of ’92” who the Fourth Doctor bumped into again during The Armageddon Factor.

It appears this may have been a genuine attempt by writer Anthony Read, who created Drax, to answer the series’ enigmatic title question through the medium of some knockabout throwaway banter. Fortunately, everyone chose to ignore this and assume it must have been a jokey nickname, which the Seventh Doctor confirmed it was in The Happiness Patrol.

Could it give some clue to his actual name, though? After all, most nicknames bear some relation to the real thing (unless you’re Sting).

For a clue, let’s turn to The Making of Doctor Who, the series’ very first reference guide, published in 1972. Written by then-script editor Terrance Dicks and regular scripter Malcolm Hulke (thus giving it a certain legitimacy), it breezily claimed, casual as you like, that the Doctor’s real name was δ³Σx². So Theta Sigma may well be a hilarious variation of this. (I couldn’t possibly tell you, as it’s all Greek to me.)

The Doctor's name is... The Oncoming Storm, The Beast, Predator of the Daleks, The Great Exterminator, The Destroyer of Worlds, etc

Names given to the Doctor by his various enemies. They’re pretty cool names, actually. If they really wanted to annoy him, they should call him Custard Face, or something.

The Doctor's name is... Something unpronounceable

The Sixth Doctor once told Peri she wouldn’t be able to pronounce his real name. Though this was on Radio 4, so may not be canon. Also, the Sixth Doctor had a very low opinion of people, and Americans in particular, so was possibly just being rude.

Though later on, Peter Capaldi's Twelfth Doctor suggested in his final moments that his name was largely incomprehensible, unless you were a child with your "heart in the right place" so who knows - maybe it wasn't just a healthy dose of xenophobia from the Sixth Doctor after all...

The Doctor's name is... Doctor Who

OK, here’s the biggie. If the Doctor’s real name ever has been spoken on screen, then most of the evidence points towards his/her name being the same as the one on the tin (or the DVD box, anyway): Doctor Who.

Firstly, as far back as 1966, in the William Hartnell story The War Machines, supercomputer Wotan declared “Doctor Who is required, bring him here”.

Yes, we know the real reason for this is because the writer hadn’t read his brief properly, or hadn’t actually ever watched the show, but now it’s out there, we can’t unhear it.

Wotan could be wrong, of course – a case of “computer says Who” – but it was far from an isolated incident. The following year, Patrick Troughton’s Doctor, masquerading as a German, used the name ‘Doctor von Wer’ (Doctor of Who), and a few weeks later signed a message with “Dr W.” What could all that possibly mean?

That’s to say nothing of all the “Doctor? Doctor who?” gags over the years. And let’s not forget the full text of Dorium Maldovar’s warning: “The first question. The question that must never be answered, hidden in plain sight. The question you’ve been running from all your life. Doctor who? Doctor who? Doctor who?”

Hidden in plain sight. What could be more hidden in plain sight than the name of the show, the one that comes whizzing towards you through space at the start of every episode? It’s pretty obvious, when you think about it.

Michelle Gomez's Missy certainly wanted us to believe that's the answer, calling herself Doctor Who when she stepped into the Doctor's shoes for a training exercise in 2017's World Enough and Time, and insisting afterwards that it really is his name.

"He chose it himself, trying to sound mysterious," she said. "And then he dropped the 'Who' when he realised it was a tiny bit on the nose."

Even the Doctor doesn't disagree. "You see this mad woman sitting in this chair? Her name is not Doctor Who, my name is Doctor Who."

"It's not is it?" asks a puzzled Nardole.

"I like it," replies the Doctor.

Come to think of it, so do we. And especially given the revelations of 2020's The Timeless Children, which suggested even the Doctor doesn't know the truth of her past, maybe we should just stick with it. Steven Moffat seems to like the idea anyway...

This article was previously published in 2017.

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