Today, I was taking a look at how to pronounce the name WD-40.

A quick google search dropped me here: https://www.youtube.com/watch?v=e8SwN_qw3AA

My Spanish ear is very new to the English language, but I can assure you I heard "double D forty" instead of "double-U-D-Forty", and I'm very confused.

Which one is correct?

  • 35
    As a native speaker, all of the examples in the video were saying double-U D forty. I've never heard anyone call it double-D forty. Commented Mar 21, 2022 at 21:46
  • 27
    I more frequently hear the five-syllable pronunciation as "dubyuh-dee-forty." In some parts of the U.S. (such as Texas), "dubyuh" is a very common way to pronounce "W."
    – Sven Yargs
    Commented Mar 21, 2022 at 21:47
  • 16
    It's "dubyuh-dee-forty". That's clearly what is being said in the video.
    – Hot Licks
    Commented Mar 21, 2022 at 21:53
  • 13
    @Tomás: As you may know, former Texas governor (and U.S. president) George W. Bush was nicknamed 'Dubya'; I believe that the nickname arose because people in Texas used the designation 'W' to distinguish him (George W. Bush) from his father (George H.W. Bush).
    – Sven Yargs
    Commented Mar 21, 2022 at 22:12
  • 9
    I’m voting to close this question because it seems to be based on a false premise. Partial omission of syllables is quite common in speech, more obviously in the US than the UK. Commented Mar 22, 2022 at 11:21

5 Answers 5


English speakers commonly leave out unaccented syllables in certain words. "Double you" is one of them, at least in the U.S. Look at Merriam-Webster's pronunciation of this word. They give double-you /ˈdʌbəlˌju/ , dubba-you /ˈdʌbəˌju/ , dub-you /ˈdʌb.ju/, or dub-ya /ˈdʌb.jə/. The speaker in the video is saying dub-you D forty and not double D forty. All these pronunciations are correct.

There are many other words where we leave out unaccented syllables, particularly when we're speaking fast. A few examples: comfortable also gets pronounced comfterble, probably is also pronounced probly, and interesting can be pronounced intresting.

  • 21
    I once had a girlfriend who insisted on pronouncing "W&L," short for "Washington and Lee [University]," as double-you and ell. I pointed out to her that if you pronounce it that way it's not actually shorter than saying "Washington and Lee," at which point she finally relented and started saying "dubyanell" like everyone else. In the 90s is was quite common for people, perhaps unwittingly, to speak only two thirds of "double-you double-you double-you" in URLs. Then I moved to Amsterdam in 1999 where it's /ʋe ʋe ʋe/. So much easier!
    – phoog
    Commented Mar 23, 2022 at 11:45
  • 14
    Sadly, "www" is many more syllables than "world wide web", Commented Mar 23, 2022 at 12:51
  • 15
    @SQB I've heard and adopted "dub-dub-dub"
    – TylerW
    Commented Mar 23, 2022 at 15:09
  • 6
    @SQB which makes sextuple-you :-) Commented Mar 23, 2022 at 15:11
  • 2
    Everyone says dubya for the Bush thing regardless of whether they pronounce W-D 40 double you.
    – Lambie
    Commented Mar 25, 2022 at 16:22

There are different pronunciations in that video.

  1. (blue shirt guy) so take a company like dub-el-you-dee-for-dee
  2. (older man) a comment like "at dub-a-you-dee-for-dee there are no mistakes"
  3. (x-ray voiceover) injectable synthetic lubricant shots like dub-you-dee-for-dee for their knee
  4. (seated man) you know why it's called dub-a-you-dee-for-dee, right?
  5. (grey bearded man) you know dub-a-you-dee-for-dee, the lubricant that everybody uses

If you slow it down to quarter speed, you should be able to hear the differences. Three of them were typical (#2, 4, & 5), one was more precise than usual (#1), the other was less precise than usual (#3). All sound fine to a native ear.

So the first three are precise, normal, then less precise than normal, and the last two are both normal.

  • 5
    The transcriptions in this answer give the false impression that the pronunciation of the letter D is identical to that of the second syllable of forty. Both the consonant and the vowel are different, especially the consonant. I don't have a suggestion for a better transcription short of using IPA, but the difference ought to be noted.
    – phoog
    Commented Mar 23, 2022 at 12:02

Where did the third syllable of the letter W in WD-40 go?

My Spanish ear...

It went to the same place as the "doble" of the letter W in the car brand "BMW" in Spanish did!

In a similar way that Spanish speakers say "B M V" instead of "B M doble V", English speakers shorten "double you" to "dubbleyu" (or "dubya" in certain places in the USA) when pronouncing the letter W along with other letters, like in "WD-40", "WWW", or "WI meeting".

  • This is possibly regional. Here in Central America we call that car a "Bay Emmy"...I am not putting the IPA coz it looks like you are not familiar with it. Commented Mar 29, 2022 at 20:01
  • 1
    @Cascabel_StandWithUkraine that's interesting, I didn't know that (I'm not surprised though, as Spanish speakers south of about 39° north tend to cut off the ends of words when speaking ;-) ) Similarly, in British English, a slang name for that car was "Beamer", which confused me when I first heard it because there used to be a British car company called "BMA".
    – Aaron F
    Commented Mar 29, 2022 at 20:40
  • 1
    Absolutely...I used to work at an Institute called "British Language Centre"...but everyone in Guate called it "the British"...I think your mention of "below the latitude" was observant Commented Mar 29, 2022 at 20:45
  • 1
    @Cascabel_StandWithUkraine classic! :-D When I first moved to Spain I was surprised to hear that they called the band "The Rolling Stones" Los Rolling :-)
    – Aaron F
    Commented Mar 29, 2022 at 20:46

This happens for prosodic reasons. English is a "stress-timed" language, that is, one in which stressed syllables are roughly equally spaced. This means that the prosody of a phrase (that is, the rhythm of stressed and unstressed syllables) may cause the pronunciation of the syllables to change to fit the rhythm.

The more unstressed syllables one needs to articulate in a row, the faster they have to be articulated, and this may require more nimbleness from the tongue than the speaker is willing to supply. For example:

  • "double you" (as in "I will double you, not him") has just one unstressed syllable between the stresses, and so "you" takes its full value /juː/.
  • "double-you dee" (as in "Hamilton's initials are W. D."), has two unstressed syllables, and so "you" may get reduced to /jə/ to fit in the available time.
  • "double-you-dee forty" (as in "WD-40") has three unstressed syllables, and so one of them may need be dropped to make room for the others. The most likely one to be dropped is the "-le" in "double", which was reduced to begin with, resulting in /'dəbjədi/.

The correct pronunciation is "double-you dee forty". Anything else is just someone talking fast or with a specific regional dialect (such as in Texas, USA, where people often say "dubya" for "double-you").

I often work with chemicals, and if someone told me to order some "double D forty", I would ask for clarity before placing an order. And if they want to order a "forty double D", I would happily point them to Victoria's Secret.

Colloquially, people use all sorts of shortened forms of words, and often mispronounce words, but I assure you the correct and accepted pronunciation of the water displacing chemical formula WD-40 is "double-you dee forty".

  • 6
    Upvoted for Victoria's Secret. I'll never look at WD-40 again with the same eyes! ;-) Commented Mar 23, 2022 at 10:43
  • 15
    Had I the requisite reputation on this site, I would downvote this answer because it seems to assert, in multiple places, that there is one, true correct way to pronounce a word, and that any other pronunciation (due to regional differences or rate of speech) is incorrect or a mispronunciation. "Dub-ya-dee forty" is not an incorrect pronunciation---it is a perfectly correct pronunciation of the brand in large parts of the US. Yes, it is regional. No, that does not make it wrong
    – user439040
    Commented Mar 23, 2022 at 16:22
  • 1
    I am sorry, but this seems to be a prescriptivist answer based on a narrow field (i.e. Chemistry). It has little to do with the common pronunciation of the consumer product and household oil... and so does not not answer the question... Commented Mar 24, 2022 at 22:57
  • 1
    LOL... show me a dictionary that wasn't written as a joke that claims the preferred pronunciation of the letter W is "double D" or even "dubya". Show me a well-regarded English test that is not intended as a joke where either of those is an accepted pronunciation. Y'all are confusin' "spoken by people in some specific regions" with what is generally considered correct. The OP clearly wants to learn standard English, and did not ask for slang or some regional dialect. Commented Mar 25, 2022 at 7:11
  • 5
    This answer also seems to presuppose that the speakers in the video do say "double D forty", which they do not. @PeterShor's answer explains very clearly why they do not, and what they do say (and also helps, at least implicitly, to show why the OP may have misheard what they do say as this).
    – MikeBeaton
    Commented Mar 25, 2022 at 11:48

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.