A Unique vs An Unique

Yesterday I was reviewing a paper that had clearly been written by a non-native speaker of English. When reviewing papers I try and give as much feedback as I can, mostly as I appreciate it when reviewers do that with my papers. As well as commenting on the content I also try and correct any spelling and grammar errors that I encounter. This may be a surprise to many of you as my own level of spelling and grammar is not considered world class, but when writing or reviewing papers I seem to get a better feel for when things are right or wrong.

So I was happily reviewing the paper when I encountered a sentence that started "An unique aspect of ....". I instantly changed the an to a and then stopped. Clearly "a unique" sounds right whereas "an unique" is difficult to say, but wasn't I always taught that words starting with a vowel should be preceded by an not a?

A quick look at my copy of the OED showed that it is definitely "a unique" as it gives the example "a unique opportunity to see the spectacular Bolshoi Ballet." A longer hunt through my English textbooks (working in natural language processing I have a surprising number of books on the English language) drew a blank so I turned to the web for answers.

It looks as if the reason for "a unique" is that it isn't the starting letter that is important but rather the starting sound and the suggestion was that the word unique is pronounced yoo-neek and the constant sound means you use a not an -- although I'm not entirely convinced that yoo is a constant sound!

When I dug a little deeper I found that there are actually many more examples of this in everyday usage that I'd never noticed. For example, we say "an hour" as we don't pronounce the h and we say "an MP3 file" as we pronounce MP3 em-pee-three. No wonder non-native speakers get confused when we make up easy to remember rules and then break them at every available opportunity!

While writing this post I remembered something I overheard a few years ago at work. A non-native speaker had seen a carpet described as "shag pile" and was totally confused!