[ lep-ruh-see ]
/ ˈlɛp rə si /
Save This Word!

noun Pathology.
a chronic, mildly infectious disease caused by Mycobacterium leprae, affecting the peripheral nervous system, skin, and nasal mucosa and variously characterized by ulcerations, tubercular nodules, and loss of sensation that sometimes leads to traumatic amputation of the anesthetized part.
Smoothly step over to these common grammar mistakes that trip many people up. Good luck!
Question 1 of 7
Fill in the blank: I can’t figure out _____ gave me this gift.
Also called Hansen's disease.

Origin of leprosy

1525–35; perhaps <Medieval Latin leprōsia (recorded only as synonym for leprosarium) <Greek léprōs(is) leprosy + -ia-y3


lep·rot·ic [le-prot-ik], /lɛˈprɒt ɪk/, adjectivean·ti·lep·ro·sy, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023


What is leprosy?

Leprosy is an infectious disease that causes bumps and wounds on and under the skin that gradually spread and can cause muscle weakness, nerve damage, and paralysis. If not treated effectively, it can result in the loss of body parts and eventually death.

Leprosy is also called Hansen’s disease, which is the name preferred by many medical professionals. It’s caused by a kind of bacteria called Mycobacterium leprae. It can be cured with a treatment of antibiotics and other drugs.

Cases of leprosy have been documented since ancient times. Due to its severe effects and contagiousness, many people who have had the disease throughout history have been stigmatized and treated as outcasts.

Historically, the word leper has been used to refer to a person with leprosy. Due to the stigma, it came to be used in a more figurative way to mean an outcast or someone who is excluded, especially for behavior or opinions considered unacceptable, as in Ever since I expressed my opinion, I’ve been treated like a leper around here. However, both the figurative and literal senses of the word can be considered insensitive due to the fact that they can dehumanize those who have the disease. It is typically recommended to use a phrase like “a person with Hansen’s disease” when referring to someone with the disease.

Where does the word leprosy come from?

The word leprosy comes from the Greek word for the disease, léprōs(is). This is derived from the Greek word leprós, “scaly,” which is related to lépein, “to peel.” The first records of the use of the word leprosy in English come from around the 1500s. But descriptions of a disease thought to be leprosy date back much further—it’s even mentioned in the Bible.

Some early uses of the word leprosy were more general, referring to any disease involving scaly or discolored patches of skin. Today, though, leprosy specifically refers to a disease caused by Mycobacterium leprae. Although this bacterium can be killed with antibiotics, the skin and nerve damage that the disease can cause can be permanent, so early diagnosis is key.

Advances in the treatment of leprosy only came about in the early 1900s, due to contributions by African American chemist Alice Ball and others. In 2000, the World Health Organization declared that leprosy is no longer a public health problem on a global scale, meaning that cases of it have dropped to a low level, but hundreds of thousands of people are still diagnosed with it each year.

Hansen’s disease is named for Gerhard Hansen, the Norwegian doctor and bacteriologist who determined in the 1870s that leprosy is caused by the bacterium now known as Mycobacterium leprae.

Did you know ... ?

What are some other forms related to leprosy?

What are some synonyms for leprosy?

What are some words that share a root or word element with leprosy



What are some words that often get used in discussing leprosy?


How is leprosy used in real life?

Leprosy is typically used in a medical context, but it has a history of stigmatization, so the name Hansen’s disease is often preferred.


How to use leprosy in a sentence

British Dictionary definitions for leprosy

/ (ˈlɛprəsɪ) /

pathol a chronic infectious disease occurring mainly in tropical and subtropical regions, characterized by the formation of painful inflamed nodules beneath the skin and disfigurement and wasting of affected parts, caused by the bacillus Mycobacterium lepraeAlso called: Hansen's disease

Word Origin for leprosy

C16: from leprous + -y ³
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for leprosy

[ lĕprə-sē ]

A slowly progressive, chronic infectious disease caused by the bacterium Mycobacterium leprae, that damages nerves, skin, and mucous membranes, and can lead to loss of sensation, paralysis, gangrene, and deformity if untreated.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for leprosy

[ (lep-ruh-see) ]

A chronic and infectious disease, characterized by patches of altered skin and nerve tissue (lesions) that gradually spread to cause muscle weakness, deformities, and paralysis. Some forms of antibiotics are now used to treat this disease, and plastic surgery can help correct the deformities it causes. Also called Hansen's disease.

notes for leprosy

Leprosy has been well known since ancient times, when widespread fear of those afflicted with the disease caused them to be treated as outcasts. Today, the term leper is often used to refer to a person excluded from society.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.