(Photo: BBC America) 
Doctor Who is a show with a lot of highly potent ideas to express. And some of these concepts have proven to be irresistibly transferrable into everyday life. So much so that people who don’t actually watch the show can tell you what key terms like “TARDIS” and “Dalek” mean.
In fact, they’re used so often they have even found their way into the Oxford English Dictionary, alongside “Cybermen” and “Sonic Screwdriver.”
So while “reverse the polarity of the neutron flow” might not be tripping off your postal worker’s tongue as they go about their daily business, you can bet they would love a bag that was… oh, what’s the phrase?
1. “Bigger on the inside”

One of Doctor Who’s earliest and best sci-fi conceits is the idea of a spaceship that looks small, but is in fact, inexpressibly big inside. The TARDIS is the magic box that fulfils the dream of not only being able to travel to any space, any time, it also has enough storage inside to bring back any amount of souvenirs. It’s the kind of thing we’ve all idly dreamt of from time to time, and so when we encounter a building or a car or a purse that seems uncannily spacious, what do we say? Oh yes, “it’s like a TARDIS in here.”
2. “Police box”

This is just a short note on the nature of linear time. In the 1930s, a police box was a temporary office space for police officers, which also had a telephone that the public could use to summon help. After 1964 – with genuine police boxes being phased from use on British streets – the term “police box” referred only to a TARDIS. So much so that the handful of actual police boxes that still exist are now considered to look more like the thing they were modeled after – as in “oh look, there’s a TARDIS” – than they do like themselves.
3. “Regeneration”

When the First Doctor turned into the Second Doctor, even Doctor Who didn’t have a proper name for what had just happened. There was some reference to it being a trick the Doctor’s people had come up with, a sort of rejuvenation, but that was it. And then, at the end of the Second Doctor’s tenure, the newly-defined Time Lords merely stated that “your appearance has changed before”. But once it was fully installed to describe this change, the term “regeneration” became enormously potent. The Doctor shrugged off the previous version of himself and became someone unrecognizably different. This wasn’t a term that had previously applied to people as a verb, and now it is. The Beatles regenerated. David Bowie regenerated. Madonna regenerated.
4. “Sonic screwdriver”

There is a definite crossover between the worlds of science fiction and science fact. And that’s not really all that surprising; people who are into ideas about the application of science, have been using fiction to create a wish list of objects to invent since before the industrial revolution.
The sonic screwdriver is one of many honorable additions to this list. There are many YouTubers who claim to have managed to invent one, although not one of the same scale of complexity as the Doctor’s. But on an even bigger scale, there are dads all over the world who will pick up their tiny torches and pretend they have some form of sonic capability just to entertain their kids. The idea of a sonic screwdriver has proved to be so beguiling that it has left the context in which it was originally created and become a catchall term for the excitement of domestic science.
5. “Companion”

One of the interesting things about the most recent incarnation of Doctor Who has been swapping out the term "companion." It was a decades-old agreement that the person who travels with the Doctor is called a companion. Thirteen did not enjoy the formality of such a word, preferring the more informal “fam” to describe her three TARDIS crewmates. While companion may not be in use current day, generations have grown up knowing that a companion is someone who travels with a non-family member in a relationship that is not governed by romance. The word’s air of respectability is what rescues the Doctor from looking like a creepier old Time Lord than he/she really is.
6. “Timey-wimey”

Some of the gibberish in Doctor Who has proven to be surprisingly memorable. In fact, you could say the best weird phrases have lasted longily long. In ”Blink,” Ten has to describe nonlinear time using non-specific language, and ends up burbling like a four-year-old. And that’s because quantum physics is weird. The tiny things that exist on a quantum level make no sense to the physics that we understand at our relatively gigantic level, which only reinforces the suspicion that physicists are just making stuff up as they go along. “Timey wimey“ is a perfect way to describe something that is adjacent to the specifics of physical time, but not in any way held by its laws. It also makes scientists look like babies, and who wouldn’t love that?
7. Knock-knock Jokes
It may just be a biased view, from a Whovian perspective, but surely we can all agree that the single most famous knock-knock joke is related to our favorite show. And this is despite the fact that it has no discernable punchline:
Q: Knock knock
A: Who’s there?
Q: Doctor
A: Doctor who?
And then… nothing. A sort of “haha you said it!” fanfare and blushes all round. As a joke it’s as empty as the Master’s heart. But it is also ubiquitous. I suspect someone (can’t imagine Who) went back in time to seed the idea right at the peak of the knock-knock joke’s popularity, and that’s where it took root.
8. “EX-TER-MIN-ATE!”

One of the most entertaining things about the design of a Dalek, is that it is so easily replicable using household appliances. They look like salt and pepper pots. Any sink plunger can be used as a stand-in Dalek arm, or eyestalk. There are items of street furniture from postboxes to dustbins all of which can be used as would-be Skaronians, given the right amount of imagination. And the things they say are even easier to copy. What’s the word that you have to use when attempting to play Daleks? What’s the Dalek catchphrase, the kill-quote? The word your jovial family members use when chasing pest controllers around the house? Ex-act-ly!
Are you going to start to incorporate these words into your everyday way of speaking!?