If light can pass through an object, or if you can see through it, it is transparent.

Is there a similar word for "air can pass through", or you can breathe through an object? This adjective would be used to describe a screen door, or certain types of fabric.

  • translucent also means that light can pass through it, but wiki explains it a little better, Transparent & Translucent and I couldn't find anything to add answer wise, other than that technically the air we breath is a liquid (fluid) so @Susan's answer is the best answer in my opinion, as permeable and transparent/translucent are all Adjectives
    – Malachi
    Commented Dec 26, 2013 at 18:50
  • I can't come up with a good answer, but it may be useful to know that transparency is used not only for light. For example, speaker grill fabric is referred to as acoustically transparent. Perhaps some more context would help us get you the word you desire?
    – altendky
    Commented Dec 26, 2013 at 20:08
  • 16
    This is English... make up a word for it. Maybe transairent.
    – user60597
    Commented Dec 26, 2013 at 21:36
  • 1
    So you want something that is the opposite of airtight then, so something that’s well-ventilated or breezy?
    – tchrist
    Commented Dec 27, 2013 at 5:44
  • There's value in Allo's answer, though permeability (perviousness implied via penetrability) has been mentioned, it is a relief to know that German has the word for it - luftdurchlässig albeit at the cost of being almost unpronounceable. dict.cc/german-english/luftdurchl%C3%A4ssig.html
    – user60655
    Commented Dec 27, 2013 at 9:22

17 Answers 17


permeable if the pores are small

allowing liquids or gases to pass through; capable of being permeated; penetrable; especially: having pores or openings that permit liquids or gases to pass through

breathable if it's a fabric

Permitting air to pass through: a breathable fabric.

I don't know what to call this property in a screen door...

apologies to @James McLeod - I didn't read the entire question and jumped on permeable.

  • 2
    I would say that, technically, a screen door would be considered permeable, although that property is usually implied and would most likely never have to be defined. Another option when it comes to doors/windows/etc. would be "drafty." I usually hear that term used to describe air coming through a building's fixture. Commented Dec 26, 2013 at 17:28
  • 4
    "Drafty" to me indicates a shortcoming. "Airy" is similar but implies that it is by design.
    – Steve H.
    Commented Dec 26, 2013 at 17:41
  • 8
    Since "permeable" also can apply to various substances, you might want to qualify it as "air-permeable" Commented Dec 26, 2013 at 18:21
  • 1
    PTFE does not let air flow through as it is also considered windproof, yet it is the heart of most waterproof yet breathable jackets. All my experience with the use of breathability of fabrics refers its ability to pass water vapor (even if by condensation and re-evaporation). Most easily this is achieved with a fabric that also allows air flow but that is not what I have observed to be the defining characteristic.
    – altendky
    Commented Dec 26, 2013 at 20:07
  • 1
    permeable is the first thing that comes to mind, however it does not imply that something has to be permeable to only air. Commented Dec 26, 2013 at 23:08

Rather to my disgust (as some who grew up reading a great deal of science fiction), the industry-accepted term for this is "breathable."

I know this is ugly and misleading, but it's the word.

  • 9
    I don’t understand the source of your disgustation here.
    – tchrist
    Commented Dec 26, 2013 at 17:08
  • 21
    @tchrist: I expect James means we only had breathable atmospheres in sci-fi, not breathable fabrics. Commented Dec 26, 2013 at 17:21
  • 7
    @FumbleFingers Breathable fabrics in a space-suit are automatically self-defeating, I should imagine.
    – tchrist
    Commented Dec 26, 2013 at 17:23
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    @tchrist: Often the suffix "able" works on a verb X to form adjective "X-able" meaning "something that can be X-ed": "eatable = something that can be eaten", "readable=can be read", "applicable=can be applied", "respectable=can be respected", "admirable=be admired", "desirable=be desired", "tolerable=be tolerated", "acceptable=be accepted", "conceivable=be conceived", "separable=be separated", etc. But instead of "can be breathed" (as in "breathable atmosphere"), here in fabrics "breathable = can breathe", which ("can X") does not follow the generally understood meaning of the suffix. Commented Dec 27, 2013 at 8:21
  • 2
    @JAB: There are a lot of "X-able" adjectives where X is not a verb (like miserable, formidable, hospitable): my remark was only about the cases where X is indeed a verb (and unambiguously a verb: I'd say comfortable comes from the noun comfort), in which case the productive suffix -able usually has a consistent meaning. (Your flammable and inflammable would be counterexamples if they were produced as "can flame" and "can inflame", which is not the case—*inflammable* came first, with meaning indeed (roughly) "can be inflamed", and then flammable was coined.) Commented Dec 28, 2013 at 1:58

In addition to other answers' suggestions of breathable and permeable (admittedly better suited to your use case), I'd add porous for some uses:

(of a rock or other material) having minute interstices through which liquid or air may pass.

  • 5
    Porous is related to permeable, but it's distinct - Porous means 'containing pores', but doesn't specify that the pores be interconnected such that liquid or air can move from one pore to the next. So, a material like fabric can both porous and permeable, while something like polystyrene is porous but not permeable (to water, at least). Like others have said, permeability is fluid-specific (water vs. air), but porosity is not (either it has pores or it doesn't).
    – Beejamin
    Commented Dec 27, 2013 at 1:05
  • @Beejamin: err...Best I can recollect, porous means permeable to water in material science; it admittedly has a connotation of how it's porous due to its etymology, but it's otherwise used interchangeably. Commented Dec 27, 2013 at 9:09
  • @Denis - Porous does mean containing pores. In general, it refers to the fact that a surface does not entirely exclude the absorption of liquids or gas. Rather, it allows them to be absorbed. Think of a sponge. That is the very definition of porous. It does NOT imply that it allows free passage through to the other side.
    – David M
    Commented Dec 27, 2013 at 20:17
  • Yep - @DavidM's got it. Porosity is an indicator how much capacity/free space there is in the material (how big the pores are, and what shape), and permeability is an indicator of how easily fluids can flow through the material.
    – Beejamin
    Commented Dec 27, 2013 at 20:51

A Latin based word (like so many words are) would be either

Transaerocent - Air passes through easily or without resistance.

Aeropermeable - Air can pass through, but is restricted.

Transaerodynamic- The ability for air to pass through a material.

Aerolucent - Air can partially pass through, but not completely.

Aerolucid - Air can pass through with no restriction.

I just made these up.

  • 2
    Well, every single word we use today was at some point or another made up; I for one support this endeavor.
    – IQAndreas
    Commented Dec 27, 2013 at 3:02
  • 5
    -lucent and -lucid of course take us from air to light (lux) again, which is misleading Commented Dec 27, 2013 at 11:34
  • 3
    Plus, if we're going to be pedantic (which is kinda the whole point of this site), aero is a Greek root, not Latin.
    – terdon
    Commented Dec 27, 2013 at 14:08
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    Aeropermeable is a decent word. The rest are Portminotaurs - A word I just made up. It's when you try to make a Portmanteau, but wind up with a monster!
    – David M
    Commented Dec 27, 2013 at 20:23
  • 6
    If you were going with Greek, you'd go with diapneumatic, which is parallel to diaphanous.
    – O. Jones
    Commented Dec 27, 2013 at 22:38

For example, to describe a fabric as one that air can pass through, you can use "breathability".

Quoting from wikipedia: Breathability is the ability of a fabric to allow moisture vapor to be transmitted through the material.

Air Permeability is the ability of a fabric to allow air to pass through it. While Air Permeable fabrics tend to have relatively high moisture vapor transmission, it is not necessary to be Air Permeable to be breathable.

Hope this helps one way or another.


Depending on the context, it's useful to refer to the property of allowing air through in the negative: not airtight. For example, you wouldn't refer to a drafty door as permeable or breathable, but not airtight accurately describes the fault with the door.

  • Is there such an expression as "air loose"? Commented Dec 28, 2013 at 1:24
  • No, but you can say that a door or window is leaky.
    – longneck
    Commented Dec 28, 2013 at 1:26

You may find the adjective perforated useful, because perforation usually refers specifically to one or many holes in a surface allowing something (often fluid or gaseous material) to pass through.

If someone were to mention a perforated screen door then I would immediately know what they’re referring to. Membranes can be perforated; surfaces of natural things like shells can be perforated.

I think I once read a quote from a philosopher describing the universe itself as perforated with regard to the divine. Found it!

As every pool reflects the image of the sun, so every thought and thing restores us an image and creature of the supreme Good. The universe is perforated by a million channels for his activity.
                                                                                                                                                                     — R.W. Emerson

  • The best general-purpose adjective for objects that freely allow gases to penetrate them would be perforated. Depending on what audience or what specific fabric, other words may fit the bill, but to me the natural state of fabric is that gas is expected to pass through them unless they are windproof. Technical fabrics are also classified based on porosity and air-permeability, especially for sailcloth, sail laminates and parachute fabric where their design depends upon them passing strict amounts of air for proper function.
    – bmike
    Commented Dec 26, 2013 at 23:21
  • 1
    If someone were to mention a perforated screen door... Once you say screen door perhaps it would not be necessary to specifically say perforated, as screen door by definition should have holes to let light and air through shouldn't it?
    – user13267
    Commented Dec 27, 2013 at 4:33
  • Well not necessarily, though I suspect that likely depends on what part of the English speaking world you're in. I think these types of things generally have specific/localised names. A mesh screen designed to shield an interior space from insects for example would be really common in Australia but far less important somewhere else. I live in Scandinavia and I've never seen anything remotely like a perforated screen door here. On the other hand, a similar door intended to improve security, to me, cannot seriously be referred to as permeable or perforated. It just doesn't come out right.
    – sjr
    Commented Dec 27, 2013 at 4:49

adjective would be used to describe a screen door, or certain types of fabric

As many have already stated, breathable is the correct term for fabric.

However, I don’t believe there would be any particular term to describe that quality in a screen door, considering that screen door itself already implies that air passes through said door.

  • Despite my voting for the word vented. I will say that breathable works here, too. You could easily refer to a screen door as a breathable metal mesh.
    – David M
    Commented Dec 27, 2013 at 20:09
  • 2
    @DavidM you could but no one does. :)
    – DA.
    Commented Dec 27, 2013 at 21:32
  • It's one my many talents!
    – David M
    Commented Dec 27, 2013 at 22:14


seems to be used in some kinds of technical texts since the 1940s

permeable, already in Webster 1828

PER''MEABLE, a. [L.permeo; per and meo, to pass or glide.] That may be passed through without rupture or displacement of its parts, as solid matter; applied particularly to substances that admit the passage of fluids. Thus cloth, leather, wood are permeable to water and oil; glass is permeable to light, but not to water. Webster 1828

an early example of permeable relating to air:

"...what will be the utility of arrangements by which the mere joints may be made tight, when the material itself if porous, and (by air) permeable as brick is?"
-John Vallance, Considerations on the Expedience of Sinking Capital in Railways 1825

Examples of air-permeable

"A face liner for concrete comprises wood pulp with a water-absorptive, air-permeable surface substantially nonadherent to concrete on one side of the sheet."
-Paper Trade Journal 1943

"The taller the roughness elements of the ground, or the taller and less air-permeable the vegetative cover, the higher level at which zero velocity is found."
-WS Chepil & NP Woodruff - The Physics of Wind Erosion and its Control 1963

"Interior ribs are made of a higher air-permeable fabric (MIL-C-7020, Type I) for cross-cell venting."
-Dan Poynter, The Parachute Manual: A Technical Treatise on Aerodynamic Decelerators 1984

"Conversely, water vapour and air permeable fabrics do not readily provide barriers to chemical warfare agents. Air-permeable fabrics which are ideal in hot tropical climates, allow biting insects such as mosquitos to penetrate the fabrics." Richard A. Scott, Textiles in Defence 2000


Permeable implies that fluids (scientifically gases are fluids) can diffuse through a barrier. In other words, there is a resistance to the free-flow of that fluid.

The property of allowing air to pass through a fabric mesh is Breathable. It can also be used for a screen door, as that is nothing more than a mesh made of metal.

The word you want to describe composition of the fabric or screen itself is Vented. This means that something allows the free flow of air through holes in it.

I would also put in a vote for the word Mesh. A mesh is a breathable fabric, if you are seeking a word that both describes the fabric and the act of moving air through it.

The word ventilated is not correct, as this means that something which is vented has had airflow applied to it. (I'm an anesthesiologist, the word ventilated comes up A LOT!)

  • 1
    Permeable means that some type of matter (gases are fluids: search "state of matter") can pass through a barrier. In practice, a noticeable restriction is encountered. The word you want is "vented". One of its meanings is, that something allows the largely unrestricted flow of air to pass through it. (the root of "vent" is ventus; Latin for wind) Ventilated is not correct; its use would be a multi-syllabic redundancy to vented (I'm an aircraft mechanic; and though indistinct to the untrained, the word "ventilated" is grunted a LOT among my fellow mechs., I believe... but, it is hard to tell).
    – user60703
    Commented Dec 27, 2013 at 17:58
  • Ventilated is not so easily dismissed. It is very commonly used in the vernacular to convey that openings have been made for the passing of air. "Vented" is often too specific, because people then expect proper "vent" structures. In contrast, ventilated could easily mean that someone had casually run a pencil through the top of a box a few times so that a turtle could breathe. :-)
    – Jace
    Commented Aug 29, 2017 at 20:03


Present participle of "respirar" in French and Catalan. Also saying "they actually breathe" in Let in. Pretty nifty? I like that it gives some counter weight to perspirant.

Ethereal could work.

  • I thought of ethereal too, was wondering if someone would post it. +1
    – Thomas
    Commented Dec 28, 2013 at 12:47


Which means that it allows the passing of a fluid or gas.
Breathable is not a technical word, but it depends how technical you want to make your product information for customers.

  • By the Wiktionary definition, transpiring seems to involve sourcing of the fluid or gas as opposed to simply passing it from one side to another of the material in question. You may transpire sweat, but certainly your clothing does not. At least until your clothes are wet and removed and then I would say that they are transpiring the sweat.
    – altendky
    Commented Dec 27, 2013 at 13:13


for it is something that is not air-tight.

  • 5
    Sounds more like a bad pun than an actual word.
    – IQAndreas
    Commented Dec 27, 2013 at 6:31
  • 1
    Why bad, it's surely a good joke. Mods will convert it into a comment, though. lol.
    – Kris
    Commented Dec 27, 2013 at 6:41
  • This logic is sound
    – DA.
    Commented Dec 27, 2013 at 21:33

Aerated is close, but generally means open and exposed to the air, including being surrounded by air and to an extent passing through.

It would depend on the context but provided the subject is capable of providing passage for air it would be correct.

  • 2
    I'd say that common usage for 'Aerated' implies 'containing air', particularly of liquids: Aerated water is bubbly (even though that's actually carbonation with CO2, not air), and aerated cement has bubbles formed in it while liquid. I wouldn't use aerated about fabric, though.
    – Beejamin
    Commented Dec 27, 2013 at 1:09

I think English speakers generally use the term non-airtight.


One that that no one has mentioned so far is the adjective aspiratory, which means "pertaining to or suited for aspiration".

It would be suitable because one of the meanings of aspiration is "the act of breathing".

  • Aspiration is sucking in. Not technically breathing. (Dictionaries have errors, too . . .) The act of breathing involves aspiration (or more correctly inspiration), which is an active process of sucking in air. Certainly would not apply to a fabric in this case.
    – David M
    Commented Dec 27, 2013 at 20:01
  • @David M: I just found two other dictionaries, one of which is the OED, that say it's the action of breathing, so perhaps you're the one in the wrong. They both also said it can also mean the removal or transfer of fluids (which would include both gases and liquids) which would be more like "sucking out".
    – martineau
    Commented Dec 27, 2013 at 21:09
  • Again. It is the action of "drawing breath" per the dictionaries I just looked up. Aspiration is an ACTIVE process. The usage the OP wants is a passive process. BTW - I am an anesthesiologist. Breathing is my stock and trade.
    – David M
    Commented Dec 27, 2013 at 21:15

In reviewing the question and since my occupation involves HVAC technology I began with the word "diffuser"; then ventilation; and finally (filtrate or filtration) seemed to answer the question from my point of view and or experience.

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