Did you make a capricious New Year’s resolution to improve your vocabulary but now fear that your innocuous idea might be an egregious mistake due to ubiquitous distractions and insidious demands on your time? Don’t despair: we’ll make it easy for you—with a list of the words that everyone else is already trying to learn!

How many of them can you define?

Judging by this list, The Free Dictionary users really like to have colorful descriptors at their disposal. All 10 of the most bookmarked words are adjectives. Curiously, nine out of the 10 end with the suffix -ous. And many of them are used to describe negative things, as in the case of “nefarious” (extremely wicked or villainous), “insidious” (spreading harmfully in a subtle or stealthy manner), “spurious” (not genuine or real), and “pernicious” (deadly or destructive).

If you have even a fleeting interest in “ephemeral,” you might have noticed that it’s the only word in the top 10 list that doesn’t end in -ous. It’s also alone in being the only word that comes from Greek.

If you had no trouble defining all 10 words, congratulations, fellow word nerd! But did you know some of their more unusual origins?

When the word “egregious” was first being used (back in the 16th century), it had an entirely different meaning. Although it now means “conspicuously bad or offensive,” it originally meant "remarkably good” or “preeminent.” That’s quite the role reversal! Its Latin roots are ē- (“out”) and -grex (“herd” or “flock”), and it was originally reserved for someone or something so great as to stand out from the crowd. Our current negative definition for “egregious” might have begun as an ironic take on this early meaning.

“Spurious” used to have a more specific meaning than it does today. Rather than describing something that is illegitimate or false, it used to mean someone of illegitimate birth.

Though now used quite broadly, “nefarious” comes from the quite specific Latin term nefās, which literally means “not divine law” (nē not + fās divine law).

“Surreptitious” means “obtained, done, or made by clandestine or stealthy means.” Naturally, it stole its second syllable from the Latin rapere, meaning “to snatch.”

And just as “insidious” things sneak up on people, its Latin root word insidiae means “an ambush.”

Now you’re all set to cruise through 2018 with some new words (and word trivia!). (Go ahead, use them to impress your friends. We don’t mind.)

What words do you want to add to your vocabulary this year? Start making a list today!