What Makes a Vowel a Vowel and a Consonant a Consonant

Mark asks: Why is “y” only sometimes a vowel? When is it a vowel and when is it a consonant?

lettersYou already know that vowels in the English alphabet are a, e, i, o, u, and sometimes y, while the rest of the letters are called consonants. But did you ever ask yourself why the letters were divided into two separate groups?

Basically, a vowel is a sound that is made with the mouth and throat not closing at any point. In contrast, a consonant is a sound that is made with the air stopping once or more during the vocalization. That means that at some point, the sound is stopped by your teeth, tongue, lips, or constriction of the vocal cords.

The difference explains why “y” is only “sometimes” a vowel. Depending on which word “y” is being used in, it can represent different sounds. In words like “myth” or “hymn,” the letter takes on a sound like a short “i” and the mouth and throat don’t close when the sound is made. However, in words like “beyond,” it acts as a bridge between the “e” and the “o,” and there is some partial closure, making “y” a consonant.

Another forgotten letter that has the same qualities as “y” is “w.” While “w” is almost always a consonant, it is considered a vowel at the end of words like “wow” or “how.” You can see for yourself when saying these words that your mouth doesn’t fully close while pronouncing the letter.

There are, of course, other differences between vowels and consonants. For instance, in English you can have vowels that are entire words, such as “a” or “I.” You won’t see a consonant that is a word by itself, however. Words in English need vowels to break up the sounds that consonants make. So, while every word has to have a vowel, not every word has to have a consonant.

There are strings of consonants that are sometimes written like full words, like “hmm.” However, these are just sounds rather than actual words. You will also find that most words in English won’t have more than three consonants in a row, because otherwise it gets to be too difficult for English-speakers to say it. There are exceptions, of course—take the word “strengths” for example, which has a string of five consonants (though it only has three consonant sounds in a row: ng, th, and s). In other languages, like Polish, long strings of consonants are more common.

Of course, there are also sounds made by consonants that can be repeated over and over without a vowel sound. If you were to repeat “z” over and over, like the sound of a buzzing bee, you would find that your mouth remains slightly open and the sound is seemingly unobstructed—so shouldn’t it fall under the “vowel” category? The letter “z,” along with the letter “s,” actually fall under a subcategory of consonants called “fricatives.” Fricatives are sounds you make by pushing air through a small gap in your teeth.

As you can see, the differences between vowels and consonants are more complex than you were probably taught in elementary school. It’s less about the letters and more about how your mouth moves when you’re saying them.

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Bonus Facts:

  • The word “vowel” comes from the Latin word vox, which means “voice.” The word “consonant” also has a Latin root, con sonare, which means “with sound.”
  • There aren’t any words in the English language that have all five vowels in a row without any consonants in between. There is one word that has five vowels, with a repeated a, in a row: Rousseauian. It means “relating to the French philosopher Jean-Jacques Rousseau.” More commonly, “queuing” also has a lengthy string of vowels, but without an “a” or an “o.”
  • There are also words in English which contain all five vowels (with consonants in between) in order. Some of these include facetious (“treating serious situations with inappropriate humour”), abstentious (“abstinent”), and caesious (“bluish or greyish green”).
  • Ever wonder why “w” is pronounced “double-u” and not “double-v?” The Roman Latin alphabet was adapted to be used for Old English. Old English had a “w” sound, but back then the alphabet didn’t have a “w.” Instead, the “v” sound was pretty close, so words that required a “w” were often represented by a “v” instead. In the 7th century, scribes started using “uu” to represent the “w” sound, which is how it got its name. However, printers used to use “vv” to represent the sound, which is how it got its shape.
  • There are very few words in the English language that have two u’s in a row, and the only two that are used frequently are “vacuum” and “continuum.”  Nearly all of the “double u” words were adapted from Latin, such as “duumvir,” meaning “each of a pair of magistrates holding joint office in ancient Rome.” A few are adapted from other languages, such as “muumuu,” a loose dress that is traditionally worn in Hawaii.
  • Just as you won’t find long strings of consonants in English, you also won’t find long strings of the same letter. No word in the English language contains more than a double letter, so you’ll never see three directly in a row. If a word seems to call for three, it will be hyphenated. For instance, the word for something without a shell is “shell-less” not “shellless.” In other cases, a letter is dropped. For instance, “seer” has only two e’s instead of the called-for “seeer” or “see-er.” The only exceptions to this rule are things like “shhh” or “brrr,” but these aren’t really words.
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  • Abstemious is my favorite word that has all 5 vowels in order. It somehow missed your list.

  • Copy edit: Vocal “cords,” not chords. (They are actual cords.)

  • There are few words that have four or more consecutive consonants in the same syllable. “Thousandths” is one of the few with five, and only because of agglutination; the root word only has two. You might find four or five consecutive across two syllables (e.g. windblown), but rarely in one.

    English says “double U”, but French says “double V”. The write up about the origin of “W” is partially right, but in ancient Rome, V was used for U when words were carved in stone, since straight lines are easier than curves. That’s also why runic languages (pre-Latin alphabet) used straight-only characters, because they didn’t have (much) paper and words were usually engraved, not written.

  • I was of the view that ‘h’ was also occasionally a vowel, as in “hot” as the sound (not atch) can be made by simply breathing out.

  • Despite the claim, shhh, brrr, and zzz are real words. They each fit the definition of a word: a single distinct meaningful element of speech or writing. The type of word they
    are is onomatopoeia: a word that suggests, resembles, or phonetically imitates a sound. Depending on how it is used in a sentence, onomatopoeia can be classified as an interjection, a noun, an adjective, or even a verb. As the pronunciation of vowels and consonants can be elongated, the elongation is expressed by repetition in the spelling of the representative letter(s) of the word. Not all spelling variations are entries in a dictionary, but their absence from the lexical tome does not mean they are not words. Shhh, brrr, and zzz are examples of onomatopoeic words that are found in some standard dictionaries.

    The claim that there are no words in the English language that has all five vowels in a row without intervening consonants is disproved. There is miaoued. The variant spelling and past-tense verb of the cry of a cat. Though not composed of each of the vowel letters, euouae and its plural hold the English language lexical record of having six vowels in a row. In certain words, each of Y and W can represent a vowel sound. The longest word in a standard English language dictionary without a representative vowel is the seven letter word tsktsks.

  • Your reason is that when mouth and throat are not fully closed in pronouncing the letters…then that letters are considered as vowels…but in the pronouncing of letter “k” the throat and mouth are also not closed. So why k is not considered as vowels????

    • at the beginning itself when u pronounce ‘k’ ,there will be a contact with tongue and upper jaw of your mouth.if u notice clearly you will feel like, when u start to pronounce that your middle part of your tongue and the upper part of your mount will be in contact.if not it will be sounding like letter’a’.