the key one

USAGE SUMMARY

The phrase "the key one" is correct and usable in written English.
It can be used to refer to the most important or essential item in a group or list. Example: "Among all the factors we considered, the key one was the project's potential for long-term sustainability."

✓ Grammatically correct

News & Media

Science

Human-verified examples from authoritative sources

Exact Expressions

60 human-written examples

But the word "rigged," or its local variations, is probably the key one on both sides of the Atlantic.

The New Yorker

There are, however, unacceptable disparities between subpopulations within the country on many infant health indicators, including the key one of infant deaths.

BMC Women's Health

The question on the essence of life as phenomenon is the key one for astrobiology, since the answer to this question determines "breadth of our outlook".

Advances in Space Research

The Texas senator has pointed to the next procedural vote in the process on Friday or Saturday -- to end debate -- as the key one in the fight.

Huffington Post

This issue is the key one.

The Guardian

The breakdown is the key one.

The Guardian - Sport

The last point is the key one.

The Guardian - Opinion

The key one is about Lord Mandelson.

The Guardian

The key one is [a requirement to] hold more capital.

The Guardian

But the question about uniforms might be the key one.

The New Yorker

But the key one was the delay in accepting that something serious was wrong.

The New Yorker

Expert writing Tips

Best practice

Use "the key one" to emphasize a single, crucial aspect among several contributing factors to highlight its importance.

Common error

Avoid using "the key one" in situations where the importance is already obvious or where a simpler adjective like "important" suffices. Overusing it can diminish its impact.

Linguistic Context

The phrase "the key one" functions as a noun phrase that identifies a particular item or aspect as being the most important or crucial among others. Ludwig AI examples showcase its use in various contexts to emphasize significance.

Expression frequency: Very common

Frequent in

News & Media

60%

Science

25%

Formal & Business

5%

Less common in

Encyclopedias

3%

Wiki

2%

Reference

1%

Ludwig's WRAP-UP

In summary, "the key one" is a common and grammatically sound phrase used to emphasize the most important element among a group. As noted by Ludwig AI, it appears most frequently in news and media and science contexts. When using this phrase, ensure that the context clearly defines the items you're choosing from and avoid overuse in overly simple scenarios. For alternative phrasing, consider using "the most important one" or "the crucial one". Understanding these nuances will help you effectively incorporate "the key one" into your writing.

More alternative expressions

Phrases that express similar concepts, ordered by semantic similarity:

the most important one

Replaces "key" with "most important", directly indicating the highest level of significance.

the crucial one

Substitutes "key" with "crucial", highlighting the critical and decisive nature of the item.

the essential one

Replaces "key" with "essential", focusing on the fundamental and necessary aspect.

the principal one

Uses "principal" instead of "key", emphasizing the primary and leading role.

the main one

Replaces "key" with "main", indicating the primary focus or concern.

the central one

Uses "central" instead of "key", highlighting the core and focal point.

the critical one

Substitutes "key" with "critical", underscoring the vital and significant aspect.

the vital one

Replaces "key" with "vital", emphasizing the indispensable and crucial nature.

the significant one

Uses "significant" instead of "key", indicating the notable and important aspect.

the foremost one

Replaces "key" with "foremost", highlighting the preeminent and leading position.

FAQs

How can I use "the key one" in a sentence?

"The key one" is used to highlight the most important element among several options. For example: "There are many factors to consider, but the "the key one" is cost."

What is a more formal alternative to "the key one"?

For more formal writing, you could use phrases such as "the most important factor", "the crucial aspect", or "the principal element".

Is it correct to say "a key one" instead of "the key one"?

While "a key one" isn't incorrect, "the key one" is generally preferred when referring to a specific, identifiable item or aspect already under discussion. "A key one" might be used when introducing a significant item without prior context.

What's the difference between "the key one" and "the main one"?

Both "the key one" and "the main one" indicate importance, but "the key one" often suggests something that unlocks or enables further progress, while "the main one" simply identifies the primary or principal element.