When I was growing up in West Peru, my four cousins lived across the road. One of them, Tom, was about my age and was a nice enough kid but a bit of a know-it-all. While outside one day, he told me to say that he was awful. Since I was a year or two older than he was, I suspected what he was up to, but went ahead and told him that he was awful anyway.

My suspicions were confirmed when he thanked me for saying that he was “full of awe” because it meant that he was great. When I told him that wasn’t what awful meant, he stuck to his guns, arguing that being called awful was in fact a compliment. Since there was no convincing him otherwise, I dropped the issue and walked away confident that he was wrong.

Or was he? Fast forward several decades to the present day when I recently came across some information at mentalfloss.com and Readers Digest (rd.com) that support my cousin’s assertion of awesomeness. Sort of.

You see, articles at both sources confirm the fact that, back in the 1300s, “aweful” did indeed refer to something that was worthy of wonder, respect and admiration. But, as some English words are wont to do, around 500 years later “awful” had changed its ways and had come to mean “something that’s specifically bad.” (“Awesome,” on the other hand, made its journey in the opposite direction, going from meaning “a feeling of terror” to one of amazement.)

So just exactly what is going on here? According to language columnist Lane Greene’s piece “Who decides what words mean?” at aeon.co, if you’re a prescriptivist, you like to dictate the way words should be used. “You smugly preen,” he says, “about the mistakes you find abhorrent.”

If, on the other hand, you’re a descriptivist, “You show off your knowledge of language changes.” And most linguists, says Greene, are descriptivists who will “point out that semantic creep is how languages work.” In other words, the definitions of some words change slowly as more and more people use them to mean something other than what they originally meant.

I think that at this point, it’s important to point out that we’re looking at words whose meanings have done a 180 from what they meant hundreds of years ago, and not at words known as contronyms or autoantonyms, which are words that have two means that are opposites of each other. You know, words like citation (an award or a ticket), mad (angry with or crazy about) or pitch (erect or throw away).

Getting back to my cousin wanting to be “awful,” according to Greene, my cousin was using the “‘etymological fallacy’ idea that a word must mean exactly what its component roots indicate.”

To illustrate this point, Greene uses “decimate,” which, he points out, “comes from the old Roman practice of punishing a mutinous legion by killing every 10th soldier (hence that ‘deci’ root).” But the meaning of decimate, he points out, has changed over the years until these days “it means something approaching ‘to wipe out utterly.’”

Next week we’ll take a closer look at some of those words whose meanings have done an about-face and continue to march. It’ll be awesome.

Jim Witherell of Lewiston is a writer and lover of words whose work includes “L.L. Bean: The Man and His Company” and “Ed Muskie: Made in Maine.” He can be reached at jlwitherell19@gmail.com.