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Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
on a purpose
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "on a purpose" is not grammatically correct and should not be used in written English.
The correct phrase is "on purpose" which means intentionally or deliberately. Example: She bumped into the table on purpose to get his attention.
⚠ May contain grammatical issues
Science
News & Media
Academia
Alternative expressions(8)
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
21 human-written examples
But from a distance, a powerful portrait emerges, the marks of color suddenly taking on a purpose.
Academia
** Unable to settle on a purpose — unable, even, to realize that he lacks one — he becomes a polite, obedient employee.
News & Media
Unable to settle on a purpose — unable, even, to realize that he lacks one — he becomes a polite, obedient employee.
News & Media
But even this obstruction, after a while, takes on a purpose.
News & Media
Conduit borrower means the obligor on a purpose investment (as defined in § 1.148-1).
Academia
Evidence in the form of experiments performed on a purpose built rig has established that tangential vibration at certain frequencies and amplitudes influences surface finish.
Human-verified similar examples from authoritative sources
Similar Expressions
39 human-written examples
Participants were instructed to press one of two buttons on a purpose-built response box, using the index finger of each hand, to indicate as quickly and as accurately as possible the type of target.
Participants were instructed to press one of two vertically positioned buttons on a purpose-built response box, using the index finger of each hand, to indicate as quickly and as accurately as possible the type of target (i.e., they were instructed to press the upper key if the arrow pointed up).
Baseline characteristics were recorded on a purpose-designed computerized database.
Science
The bands play on a purpose-built wooden stage, before an idyllic, copse-enclosed green.
News & Media
Launched in June, the stylish and contemporary OFF Seine hotel is on a purpose-built barge docked on the Seine.
News & Media
Expert writing Tips
Best practice
Always use "on purpose" to indicate intentionality. For example, "He broke the vase on purpose" is correct.
Common error
Avoid using "on a purpose" as it's grammatically incorrect. Use "on purpose" instead. For example, do not say "She did it on a purpose"; instead, say "She did it on purpose".
Source & Trust
83%
Authority and reliability
2.2/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "on a purpose" is grammatically incorrect and rarely used. Its intended function is to express intentionality or deliberation, but it fails to do so effectively due to its non-standard construction. Ludwig AI confirms this with its analysis.
Frequent in
Science
33%
News & Media
33%
Academia
33%
Less common in
Formal & Business
0%
Encyclopedias
0%
Wiki
0%
Ludwig's WRAP-UP
In summary, the phrase "on a purpose" is grammatically incorrect. The correct and commonly used phrase is "on purpose", which conveys the meaning of intentionally or deliberately. While Ludwig provides a few examples of "on a purpose" from varied sources, Ludwig AI highlights that it should be avoided in favor of its correct counterpart. Always opt for "on purpose" or other synonyms like "deliberately" or "intentionally" to ensure clarity and grammatical accuracy in your writing.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
on purpose
This alternative is the correct idiomatic form expressing intentional action.
purposely
This alternative is a synonym for "on purpose", indicating intentionality.
deliberately
This alternative is a single-word adverb emphasizing intentional action.
intentionally
This alternative is an adverb that directly indicates something done with intention.
with intent
This alternative emphasizes the mental state behind the action.
by design
This alternative suggests that something was planned or arranged intentionally.
knowingly
This alternative emphasizes awareness and intention in performing an action.
with a specific aim
This alternative focuses on the goal or objective of the action.
calculatedly
This alternative suggests that an action was carefully planned and executed.
expressly
This alternative indicates that something is done explicitly and intentionally.
FAQs
What does "on purpose" mean?
"On purpose" means intentionally or deliberately. It indicates that an action was not accidental but was done with a specific intention.
Is "on a purpose" grammatically correct?
No, "on a purpose" is not grammatically correct. The correct phrase is "on purpose".
What can I say instead of "on purpose"?
You can use alternatives like "deliberately", "intentionally", or "purposely" to convey a similar meaning.
Which is correct, "on a purpose" or "on purpose"?
"On purpose" is the correct phrase. "On a purpose" is grammatically incorrect and should be avoided.
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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
2.2/5
Expert rating
Real-world application tested