English Language & Usage Stack Exchange is a question and answer site for linguists, etymologists, and serious English language enthusiasts. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

This question already has an answer here:

Since user starts with a vowel shouldn't we use "an" ? I've seen many cases of using "a" .

share|improve this question

marked as duplicate by Roaring Fish, J.R., Carlo_R., Andrew Leach, tchrist Feb 24 '13 at 14:26

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

up vote 73 down vote accepted

From Amerenglish:

"An" goes before all words that begin with vowels:

  • An egg

With two exceptions:

When "u" makes the same sound as the "y" in you, or "o" makes the same sound as "w" in won, then "a" is used:

  • a union
  • a united front
  • a unicorn
  • a used napkin
  • a U.S. ship
  • a one-legged man
share|improve this answer
Please include a reference to your source when you cite another website literally. – Cerberus Sep 6 '13 at 17:32
Absolutely. Will do. – Benyamin Hamidekhoo Sep 6 '13 at 17:33
An user did sound incorrect; It is nice to be right. – this Jun 2 '14 at 16:44
This is missing at least one other exceptional case, when 'E' makes the same sound as the 'y' in you, like a European. This is mentioned in the link you provided. You could probably reword the exceptional cases to indicate that 'a' is used whenever the following word begins with the sound of a consonant, regardless of the actual letter. – julealgon Jun 18 '15 at 15:30

It's a because the first sound of user is not a vowel, but the consonant /j/.

share|improve this answer
Please, could someone elaborate on this? I had never heard of that and I am having trouble looking for the right keywords to search for it. – Cesar Aug 25 '14 at 10:17
‘Vowel’ and ‘consonant’ describe letters that represent vowel and consonant sounds, but they also describe the sounds themselves. A vowel is a sound made from the throat without interruption by the other vocal organs. A consonant is a sound blocked or restricted by audible friction. The initial sound of ‘user’, /j/, is interrupted by the position of the soft palate and the tongue. It is convenient to group it with the other consonants, but, because its place and manner of articulation are a little different from them, it is also known as a semi-vowel. – Barrie England Aug 25 '14 at 10:38

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