a unknown quantity

USAGE SUMMARY

The phrase "a unknown quantity" is not correct; it should be "an unknown quantity." You can use it to refer to something that is not yet understood or is unpredictable. Example: "The new technology is still an unknown quantity in the market." Alternative expressions include "an uncertain factor" and "a variable element."

⚠ May contain grammatical issues

News & Media

Science

Sports

Human-verified similar examples from authoritative sources

Similar Expressions

59 human-written examples

Bianchi would be a clean rookie, an unknown quantity as a racer, but with no baggage attached.

The New York Times

"The feeling here was that he came in as a bit of an unknown quantity," said an Obama administration official.

Independent

"Nuneaten are a bit of an unknown quantity while Braintree are in a similar position to us.

BBC

Despite the program's popularity, it is still a bit of an unknown quantity to some students.

The New York Times

Racing for the first time in the New York City Marathon, Gebrselassie will be considered both a favorite and an unknown quantity.

The New York Times - Sports

"The challenge for the police is that some of this is a bit of an unknown quantity.

BBC

Critics may have used the term "N > 2," he explained, with N (a signifier for an unknown quantity) referring to Xi's possible terms in office. .

Huffington Post

"She said that every person is given a card," suggesting a gift card with an unknown quantity in it.

The New York Times - Sports

It will be a splashy start to an unknown quantity.

The New York Times - Sports

But it's a pricey affair for an unknown quantity.

The Guardian - Money

Cassara was an unknown quantity, and a few key players transferred.

The New York Times - Sports

Expert writing Tips

Best practice

Use this expression to describe people, teams or projects that lack a documented track record, especially in high-stakes environments like professional sports or politics.

Common error

A common mistake is focusing on the letter rather than the sound. Even if a word starts with a consonant that sounds like a vowel (e.g. "an hour"), or a vowel that sounds like a consonant (e.g. "a university"), the sound dictates the article. In the case of "a unknown quantity", the mistake is clearly audible and should be corrected to avoid looking unprofessional.

How to use

Learn how to use "a unknown quantity" with practical examples and tips.

How to use

Linguistic Context

The phrase "a unknown quantity" is a non-standard noun phrase. In typical usage, as shown by Ludwig, it is intended to function as a subject complement or direct object to describe a person or thing with an unpredictable nature. However, it fails the basic English rule of phonetic concord between the indefinite article and the following adjective.

Expression frequency: Missing

Frequent in

News & Media

65%

Sports

25%

Science

10%

Less common in

Formal & Business

5%

Social Media

3%

Academia

2%

Ludwig's WRAP-UP

The search results from Ludwig clearly demonstrate that while the concept of "an unknown quantity" is widely used across the most prestigious publications in the world, the specific phrasing "a unknown quantity" is a grammatical error. Every reliable source provided in the Ludwig AI data—ranging from The New York Times to The Guardian—uses the correct indefinite article "an". This phrase is essential for describing the unpredictable elements in sports, politics, and science. To maintain credibility in your writing, you should always ensure the article matches the vowel sound of the following word, making ""an unknown quantity"" the only acceptable choice.

More alternative expressions

Phrases that express similar concepts, ordered by semantic similarity:

an unknown quantity

Corrects the grammatical error by using the proper indefinite article before a vowel sound

a wildcard

Uses a more idiomatic and informal term for something unpredictable

an unproven entity

Suggests a more formal tone often used in business or sports contexts

a dark horse

Specifically refers to a candidate or competitor about whom little is known but who might succeed

a question mark

Metaphorical expression used to highlight uncertainty

an unpredictable factor

Focuses on the element of surprise or lack of consistency

an enigma

Implies a deeper level of mystery or difficulty in understanding

a new face

Commonly used in social or professional contexts to describe someone recently introduced

an uncertain element

A neutral alternative focusing on the lack of certainty

a mysterious variable

Adds a nuance of mystery, often used in more narrative or scientific settings

FAQs

Is it correct to say "a unknown quantity"?

No, it is grammatically incorrect. You should use ""an unknown quantity"" because "unknown" begins with a vowel sound.

What is the meaning of "an unknown quantity"?

It refers to a person or thing whose abilities, powers or effects are not yet known or understood. Alternatives include "a wildcard" or "a dark horse".

Can I use "a unknown quantity" in a business report?

You should definitely avoid "a unknown quantity" in formal writing. Instead, use "an unproven entity" or the corrected ""an unknown quantity"" to maintain professional standards.

What is a synonym for an unpredictable person?

Depending on the context, you can use "an enigma", "a wildcard", or "an uncertain factor".