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Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
for an undefined time
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "for an undefined time" is grammatically correct and can be used in written English.
It is typically used to describe a situation or action that does not have a specific duration or end date. Example: I have been living in this city for an undefined time, as I do not have any specific plans to move elsewhere. Here, the speaker is indicating that they have been living in the city for an unspecified amount of time and do not have a set plan for how long they will continue to live there.
✓ Grammatically correct
News & Media
Science
Academia
Alternative expressions(19)
for an indefinite period
for an unspecified duration
for the foreseeable future
For the foreseeable future
for an unspecified time
for an indefinite duration
for an unspecified period
for an unlimited duration
for an undetermined amount of time
for a protracted period
without a set end date
for the time being
for an unlimited time
for an undetermined time
for an unknown time
for an undefined period
for an indefinite time
for an infinite time
for an indeterminate time
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
3 human-written examples
An Akzo Nobel spokesman, John de Munnik, said that the company would continue to receive royalty payments from Johnson & Johnson for an undefined time because it had helped Johnson & Johnson create the market for Risperdal in Europe, Argentina and Brazil.
News & Media
Norbet's message is in effect "Make Austria Great Again". He calls for closed borders in particular to Muslims, complains of the trade deals made with the EU just as Trump complains of the trade deals America has made and wants to stop all Muslims from entering US for an undefined time.
News & Media
Although G. lamblia trophozoites, cultured in modified PEHPS medium, provide lower yields than the ones obtained in TYI-S-33, the yields in modified PEHPS are sufficient to maintain G. lamblia strains in a stable and reliable culture for an undefined time.
Human-verified similar examples from authoritative sources
Similar Expressions
57 human-written examples
Positive descriptions of Arabs referred mainly to undefined situations, in an undefined time, either in the desert or in an undefined place, often in legends about the exotic East.
Academia
Again like an incubator, it provides space for an undefined amount of time.
News & Media
As part of this effort, we are testing trends clearly marked as "promoted" for an undefined period of time," a Twitter representative tells us.
News & Media
As part of this effort, we are testing trends clearly marked as "promoted" for an undefined period of time," a Twitter representative tells us.
News & Media
And worst of all, they can last for an undefined period of time, providing little visibility into when the pain will end.
News & Media
This loose body was in contact with the joint for an undefined period of time before it became embedded in the medial soft tissues.
They're there for an undefined period of time for no particular reason.
News & Media
After an emergency, our coach couldn't return to Boston for an undefined amount of time, and the recent weeks had been chaotic, to say the least.
News & Media
Expert writing Tips
Best practice
When using "for an undefined time", ensure that the context clearly indicates the reason for the lack of a defined time period. This prevents confusion and ensures the reader understands the uncertainty is intentional and relevant.
Common error
Avoid using "for an undefined time" when a reasonable estimate can be provided. Vague language can diminish credibility if specifics are available. If there are clues about the time frame, use qualifiers like "approximately" or "potentially until" to add clarity.
Source & Trust
82%
Authority and reliability
4.1/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "for an undefined time" functions as an adverbial phrase, modifying a verb or clause by indicating the duration of an action or state. As evidenced by Ludwig, it specifies a period without a defined end.
Frequent in
News & Media
33%
Science
33%
Academia
33%
Less common in
Formal & Business
0%
Encyclopedias
0%
Wiki
0%
Ludwig's WRAP-UP
The phrase "for an undefined time" is a grammatically correct adverbial phrase used to indicate an uncertain duration. Ludwig AI confirms its acceptability in written English. While relatively rare, it appears in diverse contexts, including news, science, and academic writing. Alternatives like "for an uncertain period" or "for an indefinite duration" can provide similar meaning. Remember to use it when a specific time frame is genuinely unknown and cannot be estimated to enhance clarity and avoid ambiguity.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
for an uncertain duration
Replaces "undefined" with "uncertain", emphasizing the lack of clarity regarding the time period.
for an unspecified period
Substitutes "undefined" with "unspecified", indicating that the time frame hasn't been explicitly stated.
for an indefinite duration
Uses "indefinite" instead of "undefined", suggesting a lack of fixed limits.
for an unlimited duration
Replaces "undefined" with "unlimited", implying that there is no restriction on the time period.
for an undetermined amount of time
Uses "undetermined" and "amount of time" to express the unknown quantity of time.
for a protracted period
Emphasizes that something might last for a considerable and unspecified length of time, replacing 'undefined' with a sense of prolonged duration.
for the foreseeable future
Indicates that the situation is expected to continue for as long as one can reasonably predict.
without a set end date
Specifies the absence of a predetermined completion date.
for the time being
Suggests a temporary situation with an unknown end point.
for an open-ended period
Conveys that the duration is flexible and doesn't have a defined limit.
FAQs
How can I rephrase "for an undefined time" to sound more formal?
In formal contexts, consider alternatives such as "for an indefinite period" or "for an unspecified duration". These options maintain a professional tone while conveying the uncertainty of the time frame.
What's the difference between "for an undefined time" and "for the foreseeable future"?
"For an undefined time" simply indicates that the duration is unknown. "For the foreseeable future" implies the situation will continue as far as one can reasonably predict, suggesting a longer, though still indefinite, duration.
When is it appropriate to use "for an undefined time"?
Use "for an undefined time" when the exact duration is genuinely unknown and cannot be reasonably estimated. This is suitable for situations where future developments are unpredictable and have a direct impact on the time frame.
What are some common synonyms for "for an undefined time"?
Common synonyms include "for an uncertain period", "for an unspecified time", and "for an indefinite duration". The best choice depends on the specific context and the nuance you want to convey.
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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
82%
Authority and reliability
4.1/5
Expert rating
Real-world application tested