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Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
an one hour
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "an one hour" is not correct in written English.
The correct form is "a one hour" because "one" begins with a consonant sound. Example: "I need a one hour meeting to discuss the project details."
⚠ May contain grammatical issues
News & Media
Science
Academia
Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Human-verified examples from authoritative sources
Exact Expressions
9 human-written examples
Gianoni describes the way Blackbaud had traditionally run their Town Halls, "When I first started with the company, for the most part, you get up on the stage, in an one hour town hall you spend 45 minutes on the financials". Like most organizations, Blackbaud's previous leadership focused on the money story, not the meaning story.
News & Media
Brian Paddick, a former senior Met officer and now Liberal Democrat mayoral candidate, has pledged: Transport Targeted fare cuts, including an one hour bus ticket, a part timers' travel card and early bird discount for commuters using network before 7.30am.
News & Media
In the 5th day, we conducted an one hour discussion about the matter, followed up by a three hours exam where students used pen and paper to answer open-ended questions.
The Steve Jobs' Macworld Keynote is Apple Fanboy's Christmas, Hanukkah, Kwanzaa, and Boxing Day all rolled into an one hour event, but there isn't one scheduled this year according to the Macworld Website.
News & Media
The Steve Jobs' Macworld Keynote is Apple Fanboy's Christmas, Hanukkah, Kwanzaa, and Boxing Day all rolled into an one hour event, but there isn't one scheduled this year according to the Macworld Website.
News & Media
With this maintenance rate, the overlay can handle a churn rate in which up to 250 peers depart or 500 peers join the overlay during an one hour period, which is more than enough for our use case, in which the overlay is expected to be fairly static.
Human-verified similar examples from authoritative sources
Similar Expressions
51 human-written examples
Results of annual plant operation on a one hour basis are presented and discussed.
Science
This was a one hour programme on future markets.
News & Media
Saturday rehabilitation consisted of a one hour scheduled Physiotherapy session and a one hour scheduled Occupational Therapy session.
Science
I'd like to write a one hour drama for TV because I'm a huge one hour drama fan.
News & Media
Studies show this is equivalent to a one hour jog.
Academia
Expert writing Tips
Best practice
Always use "a" before "one" when referring to a duration of time because "one" begins with a consonant sound. Instead of writing "an one hour meeting", write "a one hour meeting".
Common error
Avoid using the article "an" before words that start with a consonant sound, even if the first letter is a vowel written. Saying "an one hour" is a common mistake. Remember to use "a one hour" instead.
Source & Trust
83%
Authority and reliability
2.8/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "an one hour" functions as a determiner followed by a noun phrase, attempting to specify a duration of time. However, as Ludwig AI points out, the article usage is incorrect. While examples can be found, they do not represent standard English.
Frequent in
News & Media
33%
Science
47%
Academia
20%
Less common in
Formal & Business
0%
Encyclopedias
0%
Wiki
0%
Ludwig's WRAP-UP
In summary, the phrase "an one hour" is grammatically incorrect due to the misuse of the indefinite article "an" before the word "one", which begins with a consonant sound. The correct phrasing is "a one hour". While Ludwig's examples show the phrase appearing in some contexts like News & Media and Science, it should be avoided in formal writing. Alternatives such as "a one-hour period" or "sixty minutes" can provide clarity. Always ensure correct article usage for clear communication.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
a one-hour period
Replaces the indefinite article and adds 'period' for clarity.
a one hour duration
Substitutes 'duration' for 'period', maintaining similar meaning.
one hour long
Rearranges the words to emphasize the duration.
a sixty-minute interval
Replaces "one hour" with its equivalent in minutes, offering a more precise tone.
a 60-minute session
Uses a numerical abbreviation with "session" for a succinct description of time allocated.
a single hour
Emphasizes the singularity of the hour with the addition of "single."
a period of one hour
Adds "period of" to specifically define length of time.
an hour
Removes "one", which is not needed in the sentence.
sixty minutes
Offers a direct conversion of the time frame into minutes.
approximately an hour
Indicates that the time frame is close to one hour but not exact.
FAQs
Why is "an one hour" grammatically incorrect?
The phrase "an one hour" is grammatically incorrect because the word "one" begins with a consonant sound (/wʌ/), which requires the indefinite article "a", not "an". The correct phrase is /s/a+one+hour.
What's the difference between "an one hour" and "a one hour"?
"An one hour" is grammatically incorrect. "A one hour" is correct because the rule dictates using "a" before words starting with a consonant sound, and "one" begins with the /wʌ/ sound. Therefore, always use /s/a+one+hour.
Can I say something other than "a one hour meeting"?
Yes, you can use alternatives like "a /s/one+hour+long meeting", "a /s/sixty-minute+meeting", or simply "an /s/hour meeting" depending on the context.
Is "an one-hour meeting" correct?
No, "an one-hour meeting" is incorrect. The correct phrasing is "a one-hour meeting" or "a one-hour-long meeting" which follows the standard rules of English grammar.
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Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Source & Trust
83%
Authority and reliability
2.8/5
Expert rating
Real-world application tested