There are certain things you’d like to “hone” and there are things you’d like to “home in on,” but these things are not the same. However, it’s one of those pairs of words and phrases that sound so similar and have similar meanings (like further and farther or then and than) that it’s easy to mix them up. But in an effort to hone our grammar skills, we’re going to home in on the correct usages.
First, some definitions
To hone means to sharpen, refine, or perfect something over time. You can literally hone (sharpen) a blade or you can hone a skill, such as your karaoke skills or your negotiating skills.
The word home in verb form, which is the form we’re using here, means to “move or be aimed toward a target or destination with great accuracy.” It is most often followed by the words “in on,” as in, the lion is homing in on its prey.
So as a general rule, if you’re using “in on” after it, you probably need home instead of hone.
Why we’re confused in the first place
If you always feel tempted to hone in on something, you’re not alone. Merriam-Webster says it’s probably because the use of “home” as a verb is much less familiar to us than its use as a noun:
The verb home is relatively young, as words go. The noun dates to Old English, but our earliest evidence of the verb in use is from 1765, when it was used to mean “to go or return home.” Within the next hundred years the verb had developed an animal-specific sense: an animal returning to its home or birthplace was said to be “homing.” Usually the animal in question was a pigeon — in particular, a homing pigeon.
However, because the verb form is less familiar to many English-speakers and the m and n sounds are so similar, people have mistakenly used hone in often enough that many dictionaries now list it — even though there are plenty of people who consider it to be an error.
Of course, if you want to avoid the debate altogether, you could simply zero in on your target instead.