When it comes to 10 units measurement, most of us rely on the familiar metric system or the good‑old imperial foot. Yet a handful of eccentric units hide in the shadows of history, waiting to be uncovered. From a fraternity prank to reindeer bathroom breaks, these oddball measures prove that humans love to get creative when counting the world around them.

Why 10 Units Measurement Still Fascinates Us

10 A Smoot Is Equal to 5 Feet, 7 Inches

Back in 2011, a curious corner of the internet stumbled upon the Smoot while poking around Google Earth’s distance‑measuring tool. Nestled unassumingly between nautical miles and degrees, the Smoot appeared with zero explanation, sparking a wave of blog posts and amateur sleuthing to uncover its origins.

The name honors Oliver Smoot, whose own height—five feet, seven inches—became the yardstick. In 1958, while pledging a fraternity at MIT, Smoot was chosen as the human ruler for a bridge‑length experiment. The fraternity brothers laid him down, marked his head with chalk, and repeated the process until the entire span was covered.

After a marathon of chalk‑marked measurements, the bridge measured a precise 364.4 Smoots, plus an extra “ear” for good measure. The quirky story lives on, reminding us that even a simple prank can birth a lasting unit of length.

9 A Butt Is an Old‑Timey Way to Measure Wine

Ever heard someone say “that’s a buttload of cats”? While it sounds like slang for “a lot,” a butt is actually a genuine unit of volume, historically used for wine and other liquids.

One butt equals two hogsheads. A single hogshead holds about 250 liters (or 66 gallons), so a butt totals roughly 500 liters, which translates to 132 gallons. The term traces back to Italian and French roots where “boote” originally meant a boot, later evolving into a measure for wine barrels.

Interestingly, the exact size of a hogshead has varied over time and geography—some sources list it at 54 gallons, others at 66. In the United States, the butt settled at about 126 gallons, explaining why the unit fell out of everyday use.

8 Slug Is a Unit of Mass

Don’t let the slimy critter fool you—a slug is also a legitimate unit of mass in the Imperial system. One slug weighs about 32.2 pounds (or 32.17 pounds at sea level), making it a handy conversion for physicists dealing with force and acceleration.

The confusion often stems from the fact that a pound measures force, not mass. In everyday life we equate pounds with weight, but in physics a pound represents the force needed to accelerate one slug by one foot per second squared. This distinction is rarely needed outside scientific circles, yet it underpins many engineering calculations.

7 The Word Megadeath Refers to Nuclear Death Tolls

While the 1980s metal band Megadeth might be the first thing that comes to mind, the term actually serves as a grim statistical unit. A megadeath quantifies death tolls in millions, typically used by analysts evaluating potential nuclear fallout.

For example, if a city of 2.6 million residents were wiped out by a nuclear strike, the casualty count would be recorded as 2.6 megadeaths. The starkness of the term underscores the sheer scale of loss that policymakers grapple with when modeling catastrophic scenarios.

6 A Cuil Is a Measure of Surreality

We toss the word “surreal” around for everything from bizarre movies to odd job interviews, but a Cuil attempts to quantify just how far beyond the ordinary something truly is. The concept was born as a tongue‑in‑cheek critique of a 2008 search engine that frequently returned absurd, unrelated results.

Each Cuil represents one level of abstraction away from reality, meaning the higher the Cuil value, the more detached the experience from the expected. Though purely theoretical, the metric pokes fun at how we sometimes measure the unmeasurable.

The search engine itself, named Cuil, claimed to index 120 billion pages before folding in 2010. Its wildly off‑base results inspired the creation of “Cuil Theory,” a playful framework for gauging absurdity in information retrieval.

5 A Noggin Is Either a Half Pint or Quarter Pint

If you love tracking how much you drink, you might have encountered the term “noggin.” Historically, a noggin has floated between being a half‑pint and a quarter‑pint, and it’s also synonymous with the old‑fashioned gill.

In metric terms, a noggin equals roughly 142 cubic centimeters, which is about 0.6 cups or 4.8 ounces—just over three standard shots. Its ambiguous definition makes it a quirky footnote in the annals of beverage measurement.

4 Poronkusema Is How Far a Reindeer Can Walk Before It Needs to Pee

Finnish herders discovered that reindeer tend to travel a fairly consistent distance before needing to relieve themselves. This observation gave rise to the poronkusema, literally “reindeer piss,” which measures roughly 7.5 kilometers (or 4.7 miles).

The term captures a very practical aspect of nomadic life in the north, offering a natural yardstick for planning long treks. While not commonly used outside of cultural anecdotes, it remains a vivid example of how everyday animal behavior can shape language.

3 Millihelen Is a Tongue‑in‑Cheek Measurement of Beauty

Scientists with a sense of humor coined the millihelen to quantify beauty, using Helen of Troy—the face that supposedly launched a thousand ships—as the gold standard. One millihelen equals the amount of attractiveness needed to set a single ship sailing.

In practice, a score of 500 millihelens is considered average, turning the ancient myth into a modern, albeit tongue‑in‑cheek, rating system for looks. Though obviously subjective, the metric highlights how even beauty can be playfully measured.

2 A Micromort Measures a One‑in‑a‑Million Risk of Death

Where a megadeath tallies millions of fatalities, a micromort captures the opposite end of the spectrum: a one‑in‑a‑million chance of dying. During the COVID‑19 pandemic, researchers noted that illicit‑drug deaths rose to about one micromort per day, double the previous year’s rate.

Since the 1980s, micromorts have helped quantify everyday risks. Scuba diving carries roughly five micromorts, while base‑jumping jumps to about 430. Even a theoretical nuclear strike in London in 2022 was calculated at a minuscule 0.01 micromorts, illustrating the metric’s flexibility.

For the average young adult, a typical day carries about one micromort of risk, providing a useful baseline for comparing the danger of various activities.

1 Batman Is a Unit of Measure From the Ottoman Empire

The most unconventional unit on our list is the Batman, a weight measure dating back to the fourteenth‑century Ottoman world. Weighing in at roughly 16.7 pounds, the Batman has nothing to do with caped crusaders—it was a common trade unit across Central Asia.

Regional variations meant that a Batman could differ slightly in mass, much like today’s bushel or kilogram. Multiple Batmans could be combined to form larger, unnamed units, hinting at a sophisticated commercial system long before modern standardization.

Wars aren’t always won by traditional units fighting in strict formations, even if they still do the bulk of the work. Military commanders throughout history have experimented with unusual, specialized units that don’t fit into any conventional military role, often to great success. 

10. Ghost Army

The 23rd Headquarters Special Troops – or the ‘Ghost Army’ – was activated on January 20, 1944 as a secretive, highly-specialized unit of the US Army during WW2. Not all of them were combat specialists, or perhaps even good at fighting, as it wasn’t originally conceived as a conventional force. Comprising over 1,000 soldiers and 82 officers hired from professions ranging from art to sound design, the Ghost Army was instead responsible for large-scale deception operations, like building entire fake regiments and sending false radio messages to the Germans, usually to support conventional Allied offensives. 

It might sound something like wartime set design, though these guys were usually working right on the front lines. On top of that, they were particularly targetted by the Germans, making it one of the more dangerous positions on the European front. Still, it was a largely successful unit, especially on D-Day. By one estimate, the Ghost Army might have saved the lives of anywhere between 15,000 – 30,000 American soldiers throughout the war. 

9. Ritchie Boys

‘Ritchie Boys’ is a recently-coined term, referring to a loose group of more than 11,000 operatives trained at Camp Ritchie near Cascade, Maryland during the Second World War. Many of them had escaped from Europe due to persecution or the outbreak of the war, and their mastery of European culture and language made them invaluable assets for the Allied war effort.

The Ritchie Boys were rigorously trained in many fields, especially espionage and interrogation, and sent back to Europe to work against the Nazis. While they operated independently and more like a decentralized spy ring than an actual unit, they were still quite effective throughout the war. Ritchie Boys provided the bulk of all intelligence gathered on the Western Front on the allied side, including crucial early information about the scale of the Holocaust. 

8. Unit 9900

Unit 9900 is a special operations unit of the Israeli Defense Forces, responsible for providing intelligence to other units and carrying out covert operations. Established in the mid-1970s, it’s an elite, secretive unit that has played a significant role in a number of high-profile missions, including the assassination of Palestinian militant leaders and rescue operations. It’s also involved in gathering intelligence on a variety of topics, including terrorist activities, weapons proliferation, and foreign policy.

One of its many subunits is the Roim Rachok, which specifically seeks out individuals on the autism spectrum to tap into their unique skills and abilities, making them well-suited for tasks like identifying tiny details in raw, satellite images. According to the IDF itself, the program is still active and successful, and the unit works alongside other parts of Unit 9900 to meet Israel’s unique defense challenges. 

7. Paradogs

Paratrooper dogs played an integral role in the success of the Allied forces during the landings at Normandy. While many people would probably go ‘aww’, there was nothing cute about what they were there to do. These British dogs were trained to target enemy positions, carry supplies, and sniff out explosives wherever they could, putting them right in the middle of the action during the high- risk operation. 

A big part of their training included getting accustomed to loud explosions and flying bullets, as they were dropped alongside human paratroopers on the day of the invasion – June 6, 1944 – and experienced the same dangerous conditions as the soldiers. Sadly, not all of them made it back out alive and had to be replaced by other dogs to complete the mission. These paradogs proved to be invaluable throughout the invasion, and many were even decorated for their bravery after the war. 

6. Mamluks

The Mamluks were a military class that rose to prominence during the Islamic era in the 13th century. Originally recruited as personal bodyguards for royal members of the Ayyubid Caliphate, they gained power due to the ongoing decline of the Islamic empire at the time, especially in Egypt. From 1250 to 1517, the Mamluk dynasty would rule over much of Egypt and Syria, with Mamluk soldiers making up the bulk of its military strength. 

Unlike other unit types, the Mamluks were almost-exclusively recruited from slaves of Turkic or Caucasian origin. They were a formidable force, known for their skills and achievements on battlefields across the Middle East and beyond. The Mamluks were instrumental in repelling Mongol attacks in Egypt and Syria, as their victory at  Ayn Jalut in modern-day Israel put a decisive end to the Mongol advance westwards – something that seemed impossible for most armies at the time.

5. Monuments Men

The Monuments Men were a loose unit of 345 men and women from 13 countries, working as a part of the Monuments, Fine Arts and Archives effort launched by Allied nations in 1943. Their primary role was the documentation, preservation, and restoration of the cultural heritage of Europe, particularly artwork and infrastructure targetted by the Nazis, as they considered almost all cool types of art to be inferior.

The group included concerned citizens as well as soldiers from around the world, including curators, architects, art historians, and other academic experts. They usually worked on or near the front lines, making it a rather dangerous job for, say, an art historian. Regardless, the Monuments Men played a crucial part in the preservation and retrieval of many notable works, including the April, 1945 raid at a salt mine full of gold, art, and other Nazi valuables in Thuringia, Germany. 

4. Immortals

The Immortals – first mentioned by Herodotus in the 5th century BC – were an elite military unit of the Persian army during the Achaemenid Empire, lasting from 559-330 BC. It was made up of exactly 10,000 hand-picked soldiers, extensively trained in all forms of combat to protect the king and his family. Whenever a member died, he was replaced by another soldier in the same role and position, making it seem like the unit was immortal.

It wasn’t just a PR stunt, either. The 10,000 Immortals were a fearsome force on the battlefield, with their body armor made of overlapping bronze and iron plates like the scales of a fish, leather-covered shields of wicker and wood, and their main weapon of choice, the six-foot-long spear.

The Immortals were a largely successful fighting unit, serving in the main forces of the Achaemenid Empire until Alexander’s decisive victory at the Battle of Gaugamela in 331 BC. Despite the defeat, Alexander regarded the Immortals as an elite, respectable unit, and even attempted to keep them intact as a fighting force after his conquest.  

3. Tunnel Rats

The Tunnel Rats were a unit of US and South Vietnamese soldiers during the Vietnam War. Most of them were volunteer specialists, tasked with clearing out the vast network of tunnels in Vietnam and Laos used by the Viet Cong. Their primary roles included looking for and disabling booby traps, close-quarters combat, and intelligence gathering. 

As you can guess, it was a dangerous and terrifying job, and they were usually only equipped with bare-bones equipment like flashlights, small pistols, and knives. The tunnels were often elaborate and made of several chambers and levels, and the full extent of the network was only known to Viet Cong fighters and some locals. Apart from enemy combatants, members of the unit also had to fight off venomous snakes and other animals like bats and spiders. 

2. Potsdam Giants

Named after the city of Potsdam in what is now Germany, the Potsdam Giants were an elite unit of exclusively-tall soldiers recruited by Prussian King Frederick William I in the early 18th century. Selected for their physical strength and tall stature, the Giants were primarily used to showcase Prussian military might at parades and other public functions, though they were also a potent fighting force when needed. 

The official name of the unit was The Grand Grenadiers of Potsdam, and many historians have also called it an early experiment in eugenics. To maintain the regiment, Frederick William experimented with selective breeding techniques – like only mating existing members with tall women. He also had a specialized rack to stretch the soldiers to make them even taller, which sometimes resulted in their deaths, as one would reasonably expect. By the time he died in 1740, there were over 2,5000 Potsdam Giants in the city, and the unit wouldn’t be fully dissolved until 1806.  

1. Sacred Band Of Thebes

The Sacred Band of Thebes was an elite military unit of the ancient Greek city-state of Thebes. Created by a Theban general called Gorgidas, it was made up of 150 gay couples, totalling to an exact 300 men. Gorgidas believed that the love between the members would make them more loyal and fearsome in battle, and rightly so, too. It was one of the more successful units of the time, first gaining fame under general Pelopidas at the Battle of Leuctra in 371 BC. 

While they might sound like the inspiration for the movie 300, the Sacred Band was actually opposed to Spartans in real life. In fact, the unit was instrumental in ending Spartan hegemony in ancient Greece, back when it was still a loose, geographical grouping of independent city states. Unfortunately, the Sacred Band would be dissolved after the Battle of Chaeronea in 338 BC, when the Macedonian army – led by Philip II and his son, Alexander – crushed the combined forces of Thebes and Athens.