Top Words of 2020

While the editors at The Free Dictionary are as thrilled as you are that it’s a new year, it’s also time for our annual look back at the most popular words from the past year. Since 2020 felt like a cruel joke, is it any wonder that “pull (one’s) leg” was searched for more than any other idiom?
Also surprising no one, many of the top search terms pertained to medicine. Read on to learn not only the origins of these words you’ve heard so many times, but also how long a quarantine was originally supposed to last, when the first human coronavirus was discovered, and what horrifying practice contributed to the adoption of hand washing in medicine.


Let’s start by breaking down a word that has probably never been said more than it was in 2020: “coronavirus.” In Latin, the word virus means “slime” or “poison,” perhaps originally a reference to snake venom. The modern understanding of “virus” came in 1892, when Russian botanist Dmitri Ivanovsky put the sap of infected tobacco plants through a filter that retained all bacteria and found that a submicroscopic infectious agent had been able to pass through the filter.
The word corona, meanwhile, means "crown" in Latin and gives the astronomical “corona” (a halo of light surrounding a celestial body) its name. The coronavirus contains a membranous envelope that appears to have spikes extending from it when viewed under an electron microscope, reminiscent of the sun’s luminous corona that becomes visible during a solar eclipse.
Side by side with an image from an electron microscope (credit: NIAID-RML), it's a bit easier to see how the sun influenced the coronavirus name.
If you’re wondering about the name "COVID-19,” that pulls letters from both “corona” (CO) and “virus” (VI), as well as “disease” (D). And the “19” refers to when the illness was first seen: 2019.
Though “coronavirus” might have been a new term to us in 2020, the strain that causes COVID-19 is far from the first one. In fact, we catch other types of coronavirus all the time—the ones that cause the common cold, for instance, which were the first human coronaviruses discovered in the 1960s. It’s surprising to think that people just 60 years ago did not know about this agent of such a common illness, but, as we noted above, people didn’t even know what viruses were until end of the 19th century!


While there are countless specific diseases, the word “disease” itself actually spells out one of their common symptoms: “dis-ease.” We have the Old French word disaise, literally meaning “a lack of” (dis-) “physical comfort” (aise), to thank for all this unpleasantness. Thus, “disease” is actually closely related to another word we do use to mean “discomfort or unease”: “malaise—“bad” (mal-) “ease” (-aise).
In the past, diseases were thought to be caused by things like supernatural phenomena and disturbances in one’s humors. A more scientific understanding didn’t start to emerge until, once again, the 19th century. Hungarian obstetrician Ignaz Semmelweis was an early pioneer in this area, and we still use the progressive practice he encouraged: hand washing. In his day, an outbreak of the highly infectious illness called puerperal fever had the ability to kill most new mothers in a hospital. Semmelweis eventually realized that doctors could limit its spread if they disinfected their hands between—wait for it—doing autopsies and tending to pregnant women.
While that whole sentence is a BIG YIKES by today’s standards, Semmelweis’s colleagues so opposed the idea of hand washing that he ended up leaving the general hospital in Vienna and moving back to Hungary. His methods were not widely accepted until after his death in 1865 and, for our sake today, thank goodness they were!


The concept of the “quarantine” as we know it today first emerged in the 17th century as the method of isolating travelers by ship so that they wouldn’t transmit any diseases to the inhabitants of their new destination. Of course, modern quarantines can vary in length (as we know all too well by now!), but the original quarantines lasted forty days. The term “quarantine” is derived from the Old Italian word quarantina, “a period of forty days,” which originally applied to times of penance or fasting. Quarantina, in turn, comes from quaranta, Italian for “forty.” This forty-day length was not chosen arbitrarily, though: most diseases incubate in less than forty days, making the threat of contamination minimal by the end of the quarantine.
Forty days stuck on a boat—yeesh. At least we’ve got Netflix!


Many people think that hospitals are scary but, based on their name, they are actually supposed to be inviting! “Hospital” comes from the Medieval Latin word hospitāle, meaning “guesthouse.” It is also related to the Latin word hospitālis, meaning “hospitable.”
Hospitals in their earliest form might have indeed been welcoming, as they were places of refuge operated by nuns. But once medicine got involved, hospitals became truly terrifying. Few patients back then survived their treatments, which predated now-common medical practices like sanitation (as we saw above with Semmelweis), anesthesia, and the formal training of nurses. (OMG.)
Anesthesia only became widespread in the late-19th century, after US dentist William T. G. Morton demonstrated the use of ether for that purpose in 1846. (Apparently, Morton’s landlord brought this idea to him, and as if that isn’t bizarre enough, Morton’s experiments on a goldfish, his dog, and himself were what eventually convinced him to try ether on a patient.) Meanwhile, in 1860, legendary nurse Florence Nightingale established a school of nursing that became a model for many others. So, we have both of them to thank for making hospitals much more hospitable places!

Pandemic and Epidemic

Pandemic and epidemic both come from the Greek word démos, meaning “people.” Their main difference is in the scope and geography of people affected: a “pan-” (“all”) “-demic” illness affects people across a wide geographic area, while an “epidemic” illness is an outbreak of disease “among the people” in a single region or locality. In short, a pandemic is a very widespread epidemic, typically one that has spread to different parts of the world.
“Epidemic” also lends its name to the scientists who study such things, “epidemiologists.” In the past, epidemiologists only focused on infectious diseases, but they now also investigate pervasive illnesses like cancer and heart disease.
Sorry, we wanted to make this section more lighthearted, we really did, but that’s 2020 for you.


Naturally, with all the upheaval in the world due to an illness, “medicine” itself was a top search term in 2020. It comes from the Latin word medērī, meaning “to heal.” (The related word medicus means “doctor.”)
While attempts to understand and treat disease have been made since ancient times, modern medicine is thought to have begun in the 17th century, with English physician William Harvey’s ability to demonstrate the circulation of blood. (Of course, this breakthrough was dismissed in his time. Seems to be a recurring theme, eh, Semmelweis?)
The 18th and 19th centuries brought further medical progress, thanks to the administering of the first vaccine in 1796 and the burgeoning understanding of germs and disease in the 1860s. Not to be outdone, the 20th century saw the discovery of the antibiotic and the DNA double helix, as well as the first successful human organ transplant. (It’s easy to forget that these monumental advances were so recent!) With each passing century, advances in medicine have given doctors more ways to heal their patients. We’ve come a long way from leeches 🤢

(Dis)honorable Mention: Furlough

Of course, we’d be remiss not to include the other “everyone-is-suddenly-talking-about-this” term of 2020, “furlough.”
The term comes from the Dutch word verlof, meaning “leave” or “permission.” Originally referring to a temporary leave of absence from military service, the term became known for all the wrong reasons in 2020 because of its secondary definition, “a temporary layoff from work.” May we never have such ubiquitous need of the term again!

Ending on a Hopeful Note

So, there you have it—an interesting, if sometimes sobering, look at some of the most popular terms that were searched for in The Free Dictionary last year.
It’s no surprise that medicine dominated our collective consciousness in 2020, but take comfort in the fact that the following words were also among the top search terms: “love,” “hope,” and “care.” The human spirit is still alive and well. And you can even brighten the day of a fellow word nerd (or TV medical drama addict) by sharing this article!
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