The usual expression to indicate that a location is inside a body of water, below the surface, is “under water”. A Stack Exchange user who seems to be a native English speaker writes:

While it's reasonable to say "beneath water" or "below water," I don't think I have ever heard or seen either until just now. I would not consider those phrases to be idiomatic; if I heard either of them I'd certainly do a double-take.

Others were quick to reply with uses of “below water” and “beneath water”, for example movie titles such as Beneath Water and Life Below Water, and the United Nations sustainable development goal “Life Below Water”. Textual search in Google Books shows that “below water” is significantly less prevalent (~2–10%) than “under water”, and “beneath water” even less so, both in American English and British English, and with relatively little variation over time in the past two centuries. These figures may be somewhat inflated because the numbers for “under water” do not include the spelling “underwater”. The statistics include expressions such as “below water surface” and “beneath water bodies”, but also expressions like “under water harvesting”, so I don't think that the spurious hits affect the numbers significantly.

So “beneath water” and “below water” are overall rare, but not inexistant. How come some speakers consider them outright unidiomatic, while others consider it normal (if perhaps rare)? Is this a regional or social variation? Is there a nuance in meaning?

  • 2
    Some people are very quick to dismiss novelty and creative usage as unidiomatic. There are idioms which are nuggets of metaphor where the meaning is not always deducible from the components, and there is idiomatic which is a larger shadow of "native" language usage. There is space between them.
    – Yorik
    Commented Mar 11, 2020 at 19:25
  • 2
    FWIW: I'm the quoted user, and yes, I'm a native (American) English speaker. Regarding @Yorik's comment, what I was attempting to say is that those alternative phrases, while reasonable and understandable, feel unnatural to me as a native speaker -- as I said, they'd cause me to do a double-take. I do not view them as idioms, so I don't think there's any confusion there.
    – JakeRobb
    Commented Mar 11, 2020 at 19:31
  • 1
    As for the cited movie titles and UN goal, two of the three appear to be British English. I'll also point out that movie titles get to make use of something akin to poetic license, i.e. it's quite acceptable to use oddball phrasing for effect or attention.
    – JakeRobb
    Commented Mar 11, 2020 at 19:45
  • 1
    Finally, I'll add: I think, basing this only on my intuition as a native speaker, that "below water" and "beneath water" would be more appropriate if you were in some kind of air-filled habitat at or below the bottom of a body of water. That is to say, there is water above you, but you are not directly submerged.
    – JakeRobb
    Commented Mar 11, 2020 at 19:47
  • 1
    'Some people are very quick to dismiss novelty and creative usage as unidiomatic.' On the other hand, ELU is not about creative use of language in the here and now (try Writing.SE), but about established usage. // 'Unidiomatic' can be paraphrased as 'not the normal choice of most proficient Anglophones'. Does this alter your perspective? Commented Mar 11, 2020 at 20:11

2 Answers 2


Despite the fact that "under", "below", "beneath", and another option you've neglected, "underneath", overlap significantly in meaning, they are in practice not distributed in the same way -- "under" is far more frequent than the others, and "underneath" far less frequent, even outside of the context of water. In Spacial Prepositions and Metaphor, Frank Boers proposes that this is because while each of these prepositions have slightly different characteristics that make some of them suitable in some contexts but not others (or provide for differences in meaning -- consider the difference between "He was wearing nothing underneath his shirt" and "He was wearing nothing below his shirt"), "under" is treated as sort of a "vague default", so that it can be used in a more general sense and thus using one of the alternatives seems marked in a way that using "under" does not.

As for what these specific differences are, there are many resources that address them. Cambridge dictionary specifically instructs users not to use "below the sea" and to instead use "under the sea", because while "under" can be used when something is covering or touching something else, "below" is generally not used in this way. Their entry for below also specifically says that it is used when there is no contact between the people or things involved. English grammar.org also says that "under" is used when one thing is covered by something else (it directly cites "under the water" vs. "below the water" here) and that "below" is "mainly used in cases when an object is not directly under another". As you can see, this is far from isolated to some native speaker(s) on this StackExchange -- it's pretty well-discussed that "below" is less suitable than "under" in these contexts.

These definitions gel with my personal (native speaker) intuitions as well -- if someone said that something were "below the water", I would assume that they meant that thing was buried in the earth that rests beneath the entire body of water, because "below the water" carries implications that it is not touching the water, which not the case if it's submerged in it. Based on the comments on this question, it seems this intuition is the same for JakeRobb.

The information I can find doesn't address "beneath" much except in non-literal cases and to describe it as much more formal/literary than "below" and "under". I think it patterns like a more formal version of "below", but I don't really have any evidence to back that up.

As for why you can find examples of "below the water" even if it's generally perceived as unidiomatic on a more widespread basis, there are probably a few factors at play. One is that if you're referring specifically to the surface of the water, "below" suddenly becomes much more idiomatic, because this is usually describing something that is not touching the water's surface. "Below the surface of the water" is actually more natural-sounding, to me, than "under the surface of the water" (though mileage may vary on that). It's possible that in some contexts or for some speakers, "water" can be used with its surface being most salient, leading to "below the water" feeling more natural. It's also possible people sometimes make deliberately unconventional choices here because they're more marked and thus feel more novel/less cliche -- this would be my explanation for titles like "Life Below Water" and more poetic uses of the 'wrong' preposition. Further, not every text is written by a native speaker, and these prepositions are so similar in meaning and overlap often enough that even highly proficient non-natives could easily choose "below" in a context where most native speakers wouldn't. Most texts aren't being proofread so strictly as to change them unless it leads to actual difficulty understanding the text for native speakers (rare in this case, as the surrounding context usually makes it clear that "submerged in water" is what is meant).

  • I'm not sure how those sites decided that "below" doesn't apply when the two are touching. Basically all of the examples in the Cambridge article sound correct to me when you switch "under" and "below". Also, if there is a distinction, Cambridge should clear that up in their own definition. They make no mention of touching, and define it "in a lower position (than), under". Under seems to have connotations of "covering"; but I don't see how they conclude that "below" has connotations of "not touching or "not ccovering".
    – JMac
    Commented Mar 12, 2020 at 15:03
  • @JMac I'm not sure exactly where they get it either, but it's worth noting Boers makes the same claim (albeit couched in a lot more jargon), so it's possible a more evidence-based linguistic analysis exists somewhere that they both draw from that I just didn't find. Or perhaps they both independently looked at existing corpora to compare and contrast the uses of these prepositions. I too wish they said their methods somewhere. As for it not being in the Cambridge definition, I take that as it being a relatively subtle connotations that aren't usually included in dictionary definitions.
    – Sparksbet
    Commented Mar 12, 2020 at 18:06

below water

"When the cops arrived on the scene, the house was well below water." [mine]

Below ground, below water are used to mean below the surface of the location of the substance ground or water.

beneath water is the same idea of location:

"More than 80% of plants are found beneath water in oceans , seas and rivers."

Did you know site

The marsh dwellers also have the entrances to their houses below water.

marsh dwellers

Beavers build entrances to their lodges below water. [mine]

GOAL 14 IN ACTION To ensure conservation of life below water, we all have to take action. Get inspired here:

global goals org

The usage is not unidiomatic but must be used correctly to mean below or beneath water as a substance.

Often, the usage is very technical:

In this study, however, talik initiation near shore was observed under water depths less than 40% of the maximum measured ice thickness on all the transects and was sometimes found beneath water as shallow as 20 cm, or 13% of the maximum ice thickness

beneath water, technical example

I guess many people consider these unidiomatic off the top of their heads without bothering to think about some real examples which serve to show this idea of water as the location of the substance water as a location marker.

Another technical example:

[...]but the leaking well is only 7 inches in diameter. Experts compare it to a nurse trying to locate your vein to to draw blood—except the vein is a mile below water and then another three and a half miles under the seabed, and the operation has to be carried out with remotely operated robotic devices.

a mile below water

"The amount of life below water is amazing, even in shallow dives," said Caleb Hayes, a project manager for the new dive center.

many examples of below water

From anglers swept away, to buses with windows smashed by waves overcoming sea defences, and vast areas of countryside beneath water, the prime minister, David Cameron, has been sufficiently struck to make a link between extreme weather and climate change, in spite of his reported comments about getting rid of "green crap".

beneath water


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.