President Obama announces a shift in policy towards Cuba on Dec. 17. (Doug Mills/Reuters-Pool)

If you listened to television and/or radio commentators talk today about President Obama’s agreement with Cuba to start normalizing diplomatic relations after more than 50 years, you are more than likely to have heard what I did: That his was “an” historic decision, or “an” historic pact or “an” historic” move. Well, it wasn’t.

It was “a” historic decision, pact, move.

Obama himself didn’t make the mistake, but plenty of commentators did, so here’s a little grammar lesson for next time.

From Oxford Dictionaries:

An is the form of the indefinite article that is used before a spoken vowel sound: it doesn’t matter how the written word in question is actually spelled. So, we say ‘an honour’, ‘an hour’, or ‘an heir’, for example, because the initial letter ‘h’ in all three words is not actually pronounced. By contrast we say ‘a hair’ or ‘a horse’ because, in these cases, the ‘h’ is pronounced.

Let’s go back to those three words that tend to cause problems: historic, horrific, and hotel. If hotel was pronounced without its initial letter ‘h’ (i.e. as if it were spelled ‘otel’), then it would be correct to use an in front of it. The same is true of historic and horrific. If horrific was pronounced ‘orrific’ and historic was pronounced ‘istoric’ then it would be appropriate to refer to ‘an istoric occasion’ or ‘an orrific accident’. In the 18th and 19th centuries, people often did pronounce these words in this way.

Fowler’s Dictionary of English Usage says:

A is used before all consonants except silent ‘h’ (a history, an hour); an was formerly usual before an unaccented syllable beginning with h (an historical work), but now that the h in such words is pronounced, the distinction has become pedantic, & a historical should be said & written’ similarly an humble is no meaningless & undesirable. …

This is the 21st century and we pronounce the “h” in historic. So enough with the “an.”