Used and loved by millions
Since I tried Ludwig back in 2017, I have been constantly using it in both editing and translation. Ever since, I suggest it to my translators at ProSciEditing.

Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
peep up
Grammar usage guide and real-world examplesUSAGE SUMMARY
'peep up' is not a correct and usable part of a sentence in written English.
It is not a commonly used expression or idiom. If you want to use a phrase that expresses a similar idea, you might say, "The sun peeped out from behind the clouds."
⚠ May contain grammatical issues
Science
News & Media
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
23 human-written examples
In a previous study, Gattinoni et al. found that in patients with pulmonary ARDS (n = 12), increasing PEEP (up to 15 cmH2O) increased ERS by increasing EL whereas in patients with extra-pulmonary ARDS (n = 9), PEEP decreased ERS by decreasing ECW and EL.
Science
By the time Palmer made it to the tee, 59 years after his first appearance here, the sun was just starting to peep up from behind the clubhouse.
News & Media
"Everybody falls flat on his face, the proprietor at once takes to the hills, and when it is all over, and you cautiously peep up, you find that he has wrecked the place but got three perfect bull's-eyes".
News & Media
It's really a kind of self-contained, motorized cockpit with a seat that reclines 140 degrees, to peep up to three 27-inch monitors.
News & Media
In this pig model, the application of commonly applied levels of PEEP (up to 15 cmH2O) was not able to prevent a FRC decline caused by IAH (18 mmHg and 26 mmHg).
Science
The SRM involves a progressive increase in PEEP (up to 40 cm H2O) over several minutes with mandatory pressure control ventilation, resulting in intermittent higher pressures (55 cm H2O) for longer duration and increased alveolar recruitment compared with static recruitment methods [ 16].
Science
Human-verified similar examples from authoritative sources
Similar Expressions
37 human-written examples
With crocuses peeping up in the backyard and buds swelling on tree branches, springtime is sending harbingers.
News & Media
But where has thinking realistically got you? a little voice peeped up from the back of her brain.
News & Media
"We arrived in Ormoc with the sun peeping up and thousands of people trying to board the ferry.
News & Media
At low tide, we scrambled along to an inaccessible beach called Frank's Shore and peeped up a blowhole that led all the way to the clifftop.
News & Media
Janie wakes to see the sun rise: "He peeped up over the door sill of the world and made a little foolishness with red".
News & Media
Expert writing Tips
Best practice
When aiming for clarity, consider using more common alternatives like "peek out" or "glance upwards" instead of "peep up". These alternatives are more widely understood and less likely to be misinterpreted.
Common error
Avoid using "peep up" in formal writing or when precision is crucial. Due to its limited and inconsistent usage, it can introduce ambiguity and detract from the overall clarity of your writing.
Source & Trust
88%
Authority and reliability
2.8/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "peep up" functions as a phrasal verb, attempting to convey the action of looking quickly or cautiously, often upwards or from a hidden position. However, its non-standard usage, as noted by Ludwig AI, suggests that its function is not always clearly understood, leading to potential ambiguity.
Frequent in
News & Media
50%
Science
50%
Formal & Business
0%
Less common in
Academia
0%
Encyclopedias
0%
Wiki
0%
Ludwig's WRAP-UP
The analysis reveals that "peep up" is a phrase of questionable grammatical standing and limited usage. While it attempts to describe a quick or cautious look, Ludwig AI notes that it's not a standard expression, potentially leading to ambiguity. Predominantly found in news and media, and scientific contexts, its informal register makes it unsuitable for formal writing. Alternatives like "peek out" or "glance upwards" offer clearer and more widely accepted substitutes, making them preferable in most writing scenarios.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
peek out
Replaces "peep" with "peek", offering a more common and generally understood way to express a quick or subtle look.
glance upwards
Focuses on the upward direction of the look, using "glance" to suggest a brief observation.
look up briefly
Emphasizes the action of looking upwards in a short amount of time.
emerge slightly
Shifts the focus to a partial appearance or emergence, rather than a direct look.
rise into view
Describes the action of something becoming visible by rising.
surface gently
Highlights a delicate or gradual appearance, suitable for describing something coming into view.
take a quick look
Focuses on the act of looking but omits the upward directionality. This is a simple expression for checking something quickly.
partially reveal
Conveys the meaning of showing something slightly or not completely, but it doesn't contain the element of "looking".
show itself
Emphasizes the act of becoming visible but without the directed action of looking or peeping.
become visible
Simplifies the meaning to the event of something being seen, dropping the subtle action of "peeping".
FAQs
What does "peep up" mean?
"Peep up" generally means to look quickly or cautiously, often from a hidden position or from below. However, due to its uncommon usage, its meaning can be ambiguous.
Is "peep up" grammatically correct?
While not strictly ungrammatical, "peep up" is not a standard or widely recognized phrase in English. Therefore, it's often better to use more common alternatives for clarity.
What can I say instead of "peep up"?
You can use alternatives like "peek out", "glance upwards", or "emerge slightly" depending on the context.
When is it appropriate to use "peep up"?
The phrase "peep up" is best reserved for informal contexts or creative writing where its slightly unconventional nature can add a unique flavor. In formal or professional settings, clearer alternatives are preferable.
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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
88%
Authority and reliability
2.8/5
Expert rating
Real-world application tested