Some words the h at the beginning is effectively silent. honor/honour and honest are some of those words. Since the word begins with a vowel sound the 'an' is used before it. For other words where the h is sounded, such as hat, then the a is used. So it depends on your dialect whether the h is sounded and thus whether the an or a is used. Of course the translation I did for this one is an enormous bear which sidesteps the whole issue.
When you are standing in front of an enormous bear you tend not to worry about such things a lot.