Enormity. Myriad. Disinterested. Decimate. Anxious. You can use them according the guidelines in your dictionary and still get told you're wrong.
If you're really unlucky, you can have an instructor mark down your grade or a co-worker gossip behind your back if they wrongly think you're wrong.
You already know how to use these words. But misinformed people may look down on your usage. So, just as cautious drivers might look both ways for cross-traffic even after the light turns green, you might want to proceed with caution when using these words.
Enormity. "The kids played their game and didn't allow the enormity of the situation to distract them," a high school basketball coach told an Illinois newspaper about a recent game. He meant the match was high-stakes, of course. A big game.
Here's one of Merriam-Webster's definitions of "enormity": "a quality of momentous importance or impact; 'the enormity of the decision.'" By that standard, the coach chose his words just fine. But that isn't the first or even second definition given for "enormity."
It's the fourth and a bit of a departure from definitions No. 1 and 2, which show the traditional meanings: 1. "an outrageous, improper, vicious or immoral act … 2. the quality or state of being immoderate, monstrous or outrageous; especially: great wickedness: 'the enormity of the crimes committed during the Third Reich.'"
To traditionalists, then, "enormity" isn't about being big. It's about being bad. That's worth keeping in mind anytime you use this word.
Myriad. I was taught years ago that "myriad" is an adjective, not a noun. You can have myriad solutions to a problem, but you can't have "a myriad of" solutions. I believed this for a long time until, finally, I looked it up and learned I'd been wrong all along. It's both an adjective and a noun.
Disinterested. This one is interesting. People use it to mean "uninterested," another way of saying "not interested." But traditionalists say that, actually, "disinterested" means impartial: "If one is disinterested in a situation, he is neutral and has no selfish interest in its outcome," according to the influential 1965 guide "The Careful Writer" by Theodore Bernstein.
Like a lot of uptight language rules that were so passionately enforced in the middle part of the last century, this one is overstated. Disinterested can, dictionaries assert, mean "not interested." What's that? You think that's just dictionaries' caving in to sloppy usage? It's not. According to Merriam-Webster, "uninterested" meant "impartial" until sometime during the 18th century. That's when the word "disinterested" emerged and took over that meaning. So the mid-20th century stickler standard was itself a slide from earlier times.
Decimate. In ancient Rome, there was a time when military leaders would punish entire army units by killing one out of every 10 soldiers. That's the original meaning of decimate, with the "dec" stem a clear reference to a tenth.
Thankfully, the original sense of "decimate" doesn't have much practical application today. Instead, people use it two ways. It's used to mean "to destroy a large portion of something" or "to destroy something completely."
Traditional usage allows the former, but not the latter. "It may legitimately be used by extension to mean destroy a considerable part of," Bernstein wrote. But any further extension, like "The fire completely decimated the house," is considered improper. And that's not just old-timers talking. Neither of the two major dictionaries used in publishing today fully allows "decimate" to mean "wipe out completely." A large part of something wiped out, yes. All of it, no.