10 Fascinating Facts About the Thesaurus for National Thesaurus Day

iStock.com/LeitnerR
iStock.com/LeitnerR

Writers often turn to a thesaurus to diversify their vocabulary and add nuance to their prose. But looking up synonyms and antonyms in a thesaurus can help anyone—writer or not—find the most vivid, incisive words to communicate thoughts and ideas. Since January 18 is Thesaurus Day, we’re celebrating with these 10 fascinating facts about your thesaurus.

1. Thesaurus comes from the Greek word for treasure.

Greek lettering.
iStock

Most logophiles consider the thesaurus to be a treasure trove of diction, but the word thesaurus really does mean "treasure." It derives from the Greek word thésauros, which means a storehouse of precious items, or a treasure.

2. The plural of thesaurus is thesauruses or thesauri.

Row of old books lined up.
iStock

How do you refer to more than one octopus? People say everything from octopuses to octopi to octopodes. Similarly, many people have trouble figuring out the correct plural form of the word thesaurus. Though thesauri is technically correct—it attaches a Latin suffix to the Latin word thēsaurus—both thesauri and thesauruses are commonly used and accepted today.

3. Early thesauruses were really dictionaries.

Close-up of the term 'ideal' in a thesaurus.
iStock

Ask a French scholar in the 16th century to see his thesaurus, and he'd gladly give you a copy of his dictionary. In the early 1530s, a French printer named Robert Estienne published Thesaurus Linguae Latinae, a comprehensive Latin dictionary listing words that appeared in Latin texts throughout an enormous span of history. And in 1572, Estienne's son Henri published Thesaurus Linguae Graecae, a dictionary of Greek words. Although the Estiennes's books were called thesauruses, they were really dictionaries comprised of alphabetical listings of words with their definitions.

4. A Greek historian wrote the first book of synonyms.

Stacks of books surrounding an open book and a pair of glasses.
iStock

Philo of Byblos, a Greek historian and grammarian, wrote On Synonyms, a dictionary of synonyms that scholars consider to be the first ancient thesaurus. Dating to the late 1st century or early 2nd century CE, the book lists Greek words that are similar in meaning to each another. Sadly, we don’t know much more about On Synonyms because copies of the work haven’t survived over the centuries.

5. An early Sanskrit thesaurus was written in the form of a poem.

Sanskrit lettering.
iStock

In the 4th century CE, an Indian poet and grammarian named Amara Sinha wrote The Amarakosha, a thesaurus of Sanskrit words. Rather than compile a boring list of similar words, Amara Sinha turned his thesaurus into a long poem. Divided into three sections—words relating to the divine, the earth, and everyday life—The Amarakosha contains verses so readers could memorize words easily. This thesaurus is the oldest book of its kind that still exists.

6. A British doctor wrote the first modern thesaurus.

Portrait of Peter Mark Roget.
Thomas Pettigrew, Wikimedia Commons // Public Domain

Peter Mark Roget is the British doctor credited with authoring the first modern thesaurus. In 1805, he began compiling a list of words, arranged by their meaning and grouped according to theme. After retiring from his work as a physician in 1852, Roget published his Thesaurus of English words and phrases; so classified and arranged as to facilitate the expression of ideas and assist in literary composition. Today, Roget’s Thesaurus is still commercially successful and widely used. In fact, we celebrate Thesaurus Day on January 18 because Roget was born on this day in 1779.

7. The thesaurus has a surprising link to a mathematical tool.

Image of a vintage log log slide rule.
Joe Haupt, Flickr // CC BY-SA 2.0

The division between "words people" and "numbers people" is deep-seated. Many mathematicians may try to steer clear of thesauruses, and bibliophiles may avoid calculators, but the thesaurus is actually linked to a mathematical tool. Around 1815, Roget invented the log-log slide rule, a ruler-like device that allows users to easily calculate the roots and exponents of numbers. So while the inventor of the thesaurus was compiling words for his tome, he was also hard at work on the log-log slide rule. A true jack-of-all-trades.

8. The Oxford English Dictionary has its own historical thesaurus.

Synonyms for
iStock

In 1965, a professor of English Language at Glasgow University suggested that scholars should create a historical thesaurus based on entries in the Oxford English Dictionary. The project was a massive undertaking, as people from multiple countries worked for 44 years to compile and classify words. Published in 2009, the Historical Thesaurus to the Oxford English Dictionary contains 800,000 words organized by theme and date. The thesaurus covers words and synonyms from Old English to the present day and lets readers discover when certain words were coined and how long they were commonly used.

9. One artist turned his love of words into a series of thesaurus paintings.

Mel Bochner,
Mel Bochner, "Crazy," 2004. Francesca Castelli, Flickr // CC BY-NC-ND 2.0

In 2014, the Jewish Museum in New York showed a survey of conceptual artist Mel Bochner’s art. Bochner had incorporated words and synonyms in his paintings for years—which were collectively referred to as the thesaurus paintings—featuring word paintings and lists of synonyms on canvas. The brightly colored paintings feature different groups of English and Yiddish synonyms. According to Bochner, Vietnam and Iraq war veterans cried after seeing his thesaurus painting Die, which features words and phrases such as expire, perish, succumb, drop dead, croak, go belly up, pull the plug, and kick the bucket.

10. There's an urban thesaurus for all your slang synonym needs.

Copy of an Urban Dictionary book.
Effie Yang, Flickr // CC BY-NC-ND 2.0

Urban Dictionary helps people decipher the latest slang terms, but where should you go when you need a thesaurus of slang? Urban Thesaurus, of course. The site, which is not affiliated with Urban Dictionary, indexes millions of slang terms culled from slang dictionaries, then calculates usage correlations between the terms. Typing in the word money, for example, gives you an eclectic list of synonyms including scrilla, cheddar, mulah, coin, and bling.

12 Perfectly Spooky Halloween Decorations Under $25

Amazon/shopDisney
Amazon/shopDisney

Halloween is right around the corner—which means it’s officially time to bring out the jack-o'-lanterns, watch scary movies, buy your costume(s), and hang up your festive decorations. Although there are thousands of decorations to choose from, you don’t have to blow your budget while decking out your house or apartment in honor of the spooky season this year. With a little guidance, you'll find plenty of ways to create the perfect ambiance at home without going for broke. (And best of all, you can put the money you saved toward extra Halloween candy to stash away.)

From giant spiders to hanging ghosts and lawn decorations, here are a few of our favorite props under $25.

1. Halloween Pillow Covers (4-Pack); $17

ZJHAI/Amazon

These adorable Halloween-themed pillowcases make the perfect accessory for any couch, sofa, or mattress. Made with thick linen fabric, these are durable, sturdy, and designed to last for seasons to come. (Tip: To prevent the zipper from breaking, fold the pillow in half before inserting.)

Buy it: Amazon

2. Black Lace Spiderweb Fireplace Mantle; $12

Aerwo/Amazon

This versatile spiderweb prop is made with 100-percent polyester, and its knit lace spiderweb pattern adds a spooky touch to any home. Display it on your doorway, across your fireplace mantel, or atop your table. (It also makes a great backdrop for Halloween photo ops.)

Buy it: Amazon

3. Statement Halloween Signs; $16

Dazonge/Amazon

These festive, statement-making banners come pre-assembled, making them incredibly easy to install. They’re also weather-resistant and washable for both outdoor and indoor use. Use tape, push-pins, or weights to prevent the signs from blowing away.

Buy it: Amazon

4. Jack Skellington and Sally Plush Dolls; $23 (Each)

Disney

Celebrate your favorite holiday with a pair of adorable Jack Skellington and Sally plush dolls from Tim Burton’s The Nightmare Before Christmas. Jack stands at 28 inches tall, while Sally is a bit shorter at 21 inches. Set them up on your sofa or against the window sill for all to see.

Buy them: Disney Shop (Jack and Sally)

5. Halloween Zombie Groundbreaker; $22

Joyin/Amazon

This spooktacular zombie lawn decoration is sure to scare all of your friends, family, and neighbors alike. Made with a combination of latex, plastic, and fabric, this durable Halloween prop is sure to last for years to come.

Buy it: Amazon

6. Hanging Ghost Decoration; $14

Moon Boat/Amazon

Drape this handmade, 14-foot-long hanging ghost decoration over your porch, doorway, or window. You can also hang it outdoors over a tree or a (very tall) bush. And, since it comes pre-assembled, you won’t have to waste time constructing it yourself.

Buy it: Amazon

7. Two-Piece Hanging Ghost Set; $17

GeeFuun/Amazon

This pair of ghosts adds a whimsical touch to any home. While they’re not “scary,” per se, they certainly are adorable. Display them in your front yard, on your porch, on a lamppost, or a tree. To hang, simply tie the ribbons and bend the wires, arms, and tails.

Buy it: Amazon

8. Pumpkin String Lights; $19

Eurus Home/Amazon

Not only are these solar-powered, 33-foot-long LED string lights good for the environment, they’re also incredibly easy to install (no long, tangly power cable chords necessary). Since they’re waterproof, you can use them both indoors and outdoors. Choose from eight different light settings, including twinkling, flashing, fading, and more.

Buy it: Amazon

9. Inflatable Ghost; $22

Joiedomi/Amazon

This adorable inflatable ghost (which dons a cute-as-can-be wizard hat!) features built-in LED lights and sandbags to help it stay sturdy. It also comes complete with a plug, extended cords, ground stakes, and fastened ropes. Simply plug it in and watch it magically inflate within just a few minutes.

Buy it: Amazon

10. Graveyard Tombstones; $17

meiguisha/Amazon

Turn your front lawn into a graveyard with this six-piece set. Each tombstone is made with foam and designed to add a touch of spookiness to your space. To install, insert one holder into the bottom of the tombstone, and one into the soil. You can use these indoors, as well.

Buy it: Amazon

11. 10-Piece Skeleton Set; $24

Fun Little Toys/Amazon

This skeleton set includes a skull, hands and arms, and legs and feet—plus five stakes to hold everything in place. Each “bone” and “joint” is flexible, allowing you to prop the skeleton into different frighteningly fun poses. Simply place the stakes into the bone socket and turn clockwise.

Buy it: Amazon

12. Outdoor Spider Web; $18

amenon/Amazon

This giant, ultra-stretchy spider web spans a whopping 23 feet. It also includes a 30-inch black spider, 20 pieces of fake spiders, one hook, and one nail. Its thick polyester rope—combined with the sturdy stakes—allows the spider web to stay in place all season long. Place the hook on a wall or tree, and expand the web using the stakes.

Buy it: Amazon

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17 Scary Sayings for 'Ghost' From Across the United States

Remains/iStock via Getty Images Plus
Remains/iStock via Getty Images Plus

On Halloween, the spirits of the dead are supposed to walk the earth with the living. Whether or not you believe that, or in ghosts in general, you might want to know what you’re getting into if you hear a South Carolina native mention a plat-eye or a Maine resident warn you about swogons. Familiarize yourself with these U.S. regional slang terms for familiar spirits from the Dictionary of American Regional English (DARE).

1. Skookum

Referring to a ghost, demon, or spirit, skookum is chiefly a Northwest term and comes from a language of the Chinook Native American peoples of the Pacific Northwest. In the Northwest and Alaska, skookum as an adjective means strong, powerful, or good, while a skookum house is a jail and a skookum chuck is a turbulent channel of water.

2. Tommyknocker

More than just a Stephen King novel, tommyknocker has been used in the West since at least the early 20th century to mean a ghost that lives in a mine. It also refers to the knocking noises that said ghost is supposed to make. This ghost sense comes from the English dialect word tommyknocker meaning a “hammer used to break ore."

3. Haunt

In the South and South Midland states, a haunt or hant is a ghost or spirit. The earliest definitions of haunt weren’t ghostly at all: According to the Oxford English Dictionary (OED), the word originated in the 13th century to mean to practice habitually or to frequent a place. Around 1576, it gained the figurative meaning of memories, cares, feelings, thoughts, etc. that distract one frequently. In 1597, the term wandered into the supernatural. From Richard III: “Some haunted by the ghosts they have deposed.” Almost 300 years later, it finally came to refer to a spirit or ghost.

4. And 5. Hot Hant or Hot Steam

You might run into a hot hant or hot steam in the Lower Mississippi Valley and southern Alabama. In Ben Burman’s 1938 book, Blow for a Landing, hot hants are hot because "they’ve gone to hell.” In To Kill a Mockingbird, a hot steam is described as “somebody who can’t get to heaven, just wallows around on lonesome roads an’ if you walk through him, when you die you’ll be one too.”

6. Bugaboo

This ghostly South and South Midland expression might also refer to an imaginary monster or the devil. In use since at least 1710, the OED says the word might come from the now obscure meaning of bug, an imaginary evil spirit (the insect meaning came later), and might also be influenced by boo. Also boogerboo and bugabo.

7. Booger

Careful if someone from the South or South Midland states says you have a booger—they could mean something more frightening than a piece of snot. The word originated in the 1750s to mean a despicable man, according to the OED, and came to mean a menacing supernatural creature in the 1820s (and dried nasal mucus in 1891).

8. Duppy

In Alabama and Louisiana, you might say duppy for ghost. According to DARE, the word comes from Bube, a Bantu language of West Africa. OED’s earliest citation in English is from British historian Edward Long’s 1774 book The History of Jamaica (“Those of deceased friends are duppies”), while DARE’s is from a 1919 issue of the Journal of American Folklore: “ … the ghost-story, the tale based on a belief about ‘hants’ or ‘bugies’ or ‘duppies.’”

9. Hide-Behind

Also high-behind and nigh-behind, this term refers to a ghost or imaginary creature that always hides behind some object. Henry Tryon’s 1939 book Fearsome Critters describes the hide-behind as a 6-foot-tall “highly dangerous animal” with “grizzly-like claws.” Conveniently enough, it’s “never known to attack an inebriate.” According to Vance Randolph’s 1951 We Always Lie to Strangers: Tall Tales from the Ozarks, the monster is “a lizard as big as a bull” that “lies in wait for human beings on the trails at night.”

10. Catawampus

An imaginary monster or hobgoblin in the South and South Midland states, the word also means fierce, unsparing, and destructive, according to the OED, and originated as a humorous formation, the first part of which might have been influenced by catamount, a puma or cougar.

11. Swogon

This Maine term for a spirit might come from Swamp Swogon as quoted in Holman Day’s Up in Maine: “For even in these days P.I.’s shake / At the great Swamp Swogon of Brassua Lake./ When it blitters and glabbers the long night through,/ And shrieks for the souls of the shivering crew.” Another Maine word, swogun (also spelled swagin, swagan, and other variations) refers to bean soup.

12. Akua

In Hawaii, an akua is a god, spirit, or supernatural being. The OED has atua, which it says is a Polynesian word with the same meaning.

13. Stepney

This expression is used among Gullah speakers on the Georgia and South Carolina coasts. It could mean hunger or hard times, and may also be personified as a malevolent spirit. However, where the word comes from isn’t clear.

14. Plat-Eye

Careful of plat-eyes if you’re roaming around in South Carolina at night. These hobgoblins or malevolent spirits are said to rise out of graves. Platt-eye prowl refers to the time of night they’re said to roam.

15. Go-Devil

Another South Carolina expression, a go-devil is an evil spirit or someone made up to look like one. The term also refers to various machines and devices in agriculture, forestry, the oil industry, and logging.

16. HAG (OR HAG SPIRIT)

While commonly known as a witch, in the Southeast a hag or hag spirit might also refer to the evil spirit of a dead person. Said spirit is supposed to cause nightmares by “riding” the luckless dreamer. Hag-ridden, according to the OED, means afflicted by nightmares or oppressed in the mind.

17. RAWHEAD AND BLOODYBONES

In addition to being an excellent name for a death metal band, rawhead and bloodybones is a South and South Midland expression for a specter or hobgoblin. It’s an old term: DARE’s earliest citation in American English is from 1637, while in British English it's 1566, according to the OED. The rawhead part is terrifyingly and "typically imagined as having a head in the form of a skull, or one whose flesh has been stripped of its skin,” while bloodybones is sometimes described as a bogeyman who lurks in ponds “waiting to drown children.”