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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
on its underside
Grammar usage guide and real-world examplesUSAGE SUMMARY
The phrase "on its underside" is correct and usable in written English.
It can be used to describe the bottom surface of an object or to indicate a hidden or less visible aspect of something. Example: "The label was affixed on its underside, making it difficult to see at first glance."
✓ Grammatically correct
News & Media
Wiki
Encyclopedias
Alternative expressions(7)
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
46 human-written examples
Each carries a thin film of air on its underside; one assumes they survive the isolation from the atmosphere by staying still and allowing oxygen (colder water holds more oxygen) to diffuse into their air film.
News & Media
But she is surely right that, if Eleanor believed that Marx had fathered Freddy, the news must have turned her world upside down, revealing such nasty things on its underside, that it drastically weakened her will to live.
News & Media
The lateral line system on its underside allows it to detect the minute water jets produced by buried bivalves and spoon worms, which are then extracted via suction; the excess water is expelled through the spiracles.
Wiki
Phoenix, like the Vikings before it, had been a stationary lander, built with jets on its underside that let it descend all the way to the surface with them firing.
News & Media
The group set out from Resolute Bay in Canada on 29 July in their specially-designed boat-cum-sledge which had runners on its underside so that it could be hauled over the ice.
News & Media
A seven-foot-long banana leaf dangled over the shrine; it was weighed down, on its underside, by a giant gray slug.
News & Media
Human-verified similar examples from authoritative sources
Similar Expressions
13 human-written examples
Though it might get toasty on its undersides (if under strain), it's a great first effort at making an ultrabook of this quality.
News & Media
The common vampire bat is short-haired, with silver-gray fur on its undersides, sharply demarcated from the darker fur on its back.
Wiki
Once smooth, pour the puree through a sieve, using a wooden spoon to push it through and scrape any liquid clinging on to its underside, and return your soup to the pan.
News & Media
They scrambled as the boat overturned, and ended up sitting on its fiberglass underside.
News & Media
We give some lame excuse about how it's a glass table and we don't feel like cleaning up all the fingerprints boys will paint on it when they use its underside as a napkin, even though they have a perfectly good napkin sitting beside their plate.
News & Media
Expert writing Tips
Best practice
Use "on its underside" when you need to specifically emphasize that something is located on the bottom or unseen surface of an object. This is particularly useful when describing physical attributes or hidden features.
Common error
Avoid using "on its underside" to describe abstract or non-physical concepts. The phrase is best suited for describing tangible objects and their physical characteristics. For abstract concepts, consider using alternatives like "a hidden aspect of it" or "a less visible part of it".
Source & Trust
84%
Authority and reliability
4.6/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "on its underside" functions as a prepositional phrase, modifying a noun or pronoun by specifying location. As Ludwig AI confirms, it is widely used and grammatically correct. It indicates the position of something on the bottom surface of an object.
Frequent in
News & Media
45%
Wiki
20%
Encyclopedias
10%
Less common in
Science
10%
Formal & Business
5%
Reference
5%
Ludwig's WRAP-UP
In summary, the phrase "on its underside" is a grammatically correct and versatile prepositional phrase used to describe the location of something on the bottom surface of an object. As Ludwig AI confirms, it is widely used in diverse contexts, particularly in News & Media and Wiki. While it maintains a neutral register, more technical alternatives may be preferred in formal or scientific writing. Remember to use this phrase when describing physical attributes or hidden features and avoid it for abstract concepts.
More alternative expressions(10)
Phrases that express similar concepts, ordered by semantic similarity:
on its bottom
Replaces "underside" with "bottom", a more general term for the lower surface.
beneath its surface
Uses "beneath" to indicate something is below the visible surface, implying a hidden aspect.
on its underbelly
Employs "underbelly", often used for animals or objects with a distinct bottom.
on its lower surface
More formal and descriptive, specifying the "lower surface" instead of "underside".
at its base
Focuses on the foundational or supporting part of an object.
on the bottom of it
Simple and direct rephrasing, specifying the location.
underneath it
Uses "underneath" to denote a position directly below.
at its nether region
A more archaic or humorous way to describe the lower part of something.
on its ventral side
Technical term, primarily used in biology to refer to the lower side of an animal.
on its nether side
An older, less common way to say underside.
FAQs
What does "on its underside" mean?
The phrase "on its underside" refers to the bottom or lower surface of an object, often implying that the feature or detail being described is not immediately visible.
When is it appropriate to use the phrase "on its underside"?
It is appropriate when describing the physical location of something on the bottom surface of an object or when highlighting a hidden or less obvious aspect. For example, "The label was affixed "on its underside"".
What are some alternatives to "on its underside"?
Some alternatives include "on its bottom", "beneath its surface", or "on its underbelly", depending on the context.
Is "on its underside" formal or informal?
The phrase is generally considered neutral and can be used in both formal and informal contexts, though more technical or descriptive language might be preferred in highly formal or scientific writing.
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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
84%
Authority and reliability
4.6/5
Expert rating
Real-world application tested