A E I O U and sometimes Y, but also W?
A question that I get now and then is whether W is ever a vowel. At first, I was puzzled by this question, but it turns out that grammar books from the 19th century and earlier sometimes did include W as a vowel. I’m not sure why grammar writers stopped doing it, or when the “A, E, I, O, U, and sometimes Y” that many of us learned in school became standard, but today we’re going to learn not only when Y, and maybe even W, can be a vowel. Actually, here’s a spoiler: They’re not, and neither are A, E, I, O, and U.
So how can I possibly claim that A, E, I, O, and U are not vowels?
Sounds Versus Letters
The short answer is that vowels (and consonants, too) are the actual sounds we make when we talk, and that A, E, I, O, and U, and all the other letters of the alphabet represent those vowels and consonants. This may seem like a picky distinction, but if you’re not clear on whether you’re talking about orthography or phonetics, things can get confusing. For example, we’re used to thinking of the letter U as a vowel. As a result, countless speakers have needlessly second-guessed themselves wondering whether they should write “a university” or “an university”; “a unicorn” or “an unicorn.”
A lot of confusion could have been avoided if generations of kids had just learned that U represents a vowel in words like “umbrella” and “put,” and that it represents the sequence of the consonant “yuh” and the vowel “oo” in “university” and “unicorn”!
So various letters or combinations of letters are used to represent vowels or consonants, but in and of themselves, letters are neither vowels nor consonants. I’m sorry if that goes against what you learned in school. It goes against what I learned in school, too, but unless you’re playing Scrabble or Wheel of Fortune, it really is more sensible to think about vowels and consonants this way.
When Syllables Begin with Y or W
Now that I’ve given the simple answer, let’s deal with the real question: When does W, and for that matter Y, represent a vowel? If a syllable begins with Y or W, and the next letter represents a vowel, then Y or W almost certainly represents a consonant. In “yo” and “woe,” for example, Y and W represent consonants.
If a syllable begins with Y and the next letter represents a consonant, then the Y represents a vowel. The only examples I can think of are the elements yttrium and ytterbium, and the French name Yves [pronounced “eve”]. I see in the dictionary that there are few more borrowed or archaic words with Y representing a vowel at the beginning of a word, but they’re not worth mentioning here. And there are no syllables beginning with W in which W represents a vowel.