quid

If you find yourself in a London pub, you'll likely hear quid more often than "pounds." While "pound" is the official name of the currency, quid is the everyday slang word for a British pound, much like "buck" for a dollar. In this sense, the plural is usually still quid, as in "that'll be twenty quid." You may also meet the word in the fixed Latin phrase quid pro quo, which is used for an exchange where one thing is given for another. A less common meaning is a small piece of chewing tobacco.

The word quid is used most often as British slang for the pound sterling. In everyday speech across the UK, people say "one quid," "five quid," or "twenty quid" in the same easy way an American might say "bucks." In this money sense, the form usually stays the same in the plural, so "ten quid" sounds natural, while "ten quids" usually does not. One exception is the idiom quids in, which means being in profit or in a good position financially.

Beyond the world of money, many learners first notice the word in the phrase quid pro quo. In that fixed Latin expression, it refers to one thing given in exchange for another. In plain use, people usually talk about a favor, a service, or a deal. Depending on the situation, it can sound neutral or suggest an improper exchange, especially in legal or political talk. Still, this sense mostly appears as part of the full phrase, not as a common standalone English word.

There is also a less common meaning: a quid of tobacco, which is a small piece of tobacco meant for chewing. This use is much rarer for most modern readers, but you may still see it in older writing or in dialect use. So the word can point to money, appear inside a well-known phrase about exchange, or name a bit of chewing tobacco, with the money sense being by far the most common.