Q is the least used letter of the English alphabet. In fact, according to Oxford Dictionaries, you can expect q to account for less than a fifth of 1 percent of a piece of written English—or, put another way, only one letter in every 510 will be a q.

It might be the rarest letter at our disposal, but listed under q in the dictionary are a clutch of fantastically bizarre words. Not all of them, unfortunately, are what you could call useful or everyday terms—it’s hard to drop words like querquedule (an old name for the garganey duck) or quarkonium (a meson particle comprising a quark and its corresponding antiquark, apparently) into normal conversation—but you might have better luck with the forty quirky q-words listed here.

1. QUAALTAGH 

An old Manx word for the first person you see after you leave your front door.

2. QUACKHOOD

A 19th-century word for charlatanism, or falsehood—literally, the state of being a “quack.”

3. QUADER 

An old Scots word literally meaning “to make something square,” but which can also be used figuratively to mean “to agree with or get along with someone.”

4. QUADRAGESIMAL

Lasting 40 days, or a set of 40 things. Like this list.

5. QUADRIVIUM

An old word for a crossroads, literally a place where four roads meet. A place where three roads meet, incidentally, is a trivium. (A quadrivium was also a course offered at medieval universities, in which students learned the four "mathematical arts": arithmetic, geometry, astronomy, and music.)

6. QUADRUPLATOR

An old term from Roman law for an informer, or for someone paid to attack someone else in court. No one is quite sure where this meaning comes from, given that a quadruplator is literally someone who increases something fourfold, but it’s been suggested that there might once have been a four-part punishment for those involved.

7. QUAFF-TIDE 

“The season for drinking,” according to the Oxford English Dictionary.

8. QUAGSWAGGING

Shaking something back and forward.

9. QUAMPED 

Disappointed, downhearted. Derives from an old English dialect word, quamp, meaning “to dampen someone’s spirits.”

10. QUANDORUM 

A compliment, or a polite, well-mannered gesture or phrase.

11. QUAQUAVERSAL

Heading off in all directions, like an exploding firework.

12. QUAUMSY 

An old Scots word meaning “out of sorts,” or “slightly unwell.”

13. QUAVERY-MAVERY 

Undecided or unsure. Prevaricating over a tough decision.

14. QUEAN-CRAZED 

At one time an old word for a prostitute, quean came to be used as a nickname for any pretty young woman in the Middle Ages. A man who was quean-crazed was ultimately besotted or love-struck.

15. QUEECHERING 

Lazy, sub-standard work.

16. QUEEPLING 

Another word for the high-pitched cheep made by a duckling.

17. QUENCH-COAL 

Why call it a fire-extinguisher when you can call it a quench-coal?

18. QUEUE-PEE 

An old Yorkshire dialect word for a curl of hair on top of a child’s head.

19. QUIBOW 

A word from the far north of Scotland for the branch of a tree.

20. QUICKSTICKS 

Victorian slang for “right away” or “without delay”—as in “I’ll be there quicksticks!” Also used as a verb in 1930s slang, to mean “to escape from the police.”

21. QUICQUIDLIBET 

Literally “whatever you like,” or “nothing in particular.” Borrowed directly into English from Latin.

22. QUIDAMITY

Namelessness, anonymity.

23. QUIDDLE 

An old 17th-century word from New England, variously used to mean “to play with something idly,” “to talk at great length about something trivial,” or “to fuss over inessential, unimportant things.”

24. QUIDNUNC 

A gossip. Literally means “what now?” in Latin.

25. QUIFTING 

A gulp or mouthful of drink—a quifting-pot is a glass or tankard that holds precisely half a gill (one-eighth of a pint).

26. QUIGNOGS

An old Cornish word for pipedreams, or ridiculous thoughts or ideas.

27. QUINKINS

The dried remains or dregs of food left in the bottom of a pan—and so, metaphorically, something of very little value.

28. QUIPSOME 

Describes someone who seems constantly to make jokes and quips.

29. QUIRITATION 

Lamentation, complaining. Derives from a Latin word meaning “to protest in public.”

30. QUIRKLUM 

“A little arithmetical puzzle in which the answer depends on a catch or quibble,” according to the English Dialect Dictionary.

31. QUIRLY 

American slang, from the 1930s, for a hand-rolled cigarette.

32. QUISLE 

The verb form of quisling (named after Norwegian Second World War traitor Vidkun Quisling), ultimately meaning “to betray your country” or “to collaborate with an enemy.”

33. QUISQUILIAN 

Worthless or pointless, literally “comprised of rubbish.”

34. QUISQUOUS 

A Scots word describing something tricky or baffling, or a subject that can’t be broached easily—the elephant in the room.

35. QUIZZEE 

As well as being a word for the person who answers the questions in a quiz, in 19th-century American slang a quizzee was the butt of a joke.

36. QUIZZITY 

Strangeness, oddity.

37. QUOBBLED 

When your hands and fingers wrinkle up after they’ve been in water for a long time, then they’ve quobbled.

38. QUOMODOCUNQUIZE 

Taken from a word coined by the Scottish writer and scholar Thomas Urquhart in 1652, to quomodocunquize is to make money by whatever means possible.

39. QUOP

Also spelled quapp or quob, an old dialect word meaning “to throb with pain.”

40. QUOTATIOUS 

Describes someone who likes to drop quotations into their everyday conversations.