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Synonyms

contagious

American  
[kuhn-tey-juhs] / kənˈteɪ dʒəs /

adjective

  1. capable of being transmitted by bodily contact with an infected person or object.

    contagious diseases.

  2. carrying or spreading a contagious disease.

  3. tending to spread from person to person.

    contagious laughter.


contagious British  
/ kənˈteɪdʒəs /

adjective

  1. (of a disease) capable of being passed on by direct contact with a diseased individual or by handling clothing, etc, contaminated with the causative agent Compare infectious

  2. (of an organism) harbouring or spreading the causative agent of a transmissible disease

  3. causing or likely to cause the same reaction or emotion in several people; catching; infectious

    her laughter was contagious

"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

contagious Scientific  
/ kən-tājəs /
  1. Capable of being transmitted by direct or indirect contact, as an infectious disease.

  2. Bearing contagion, as a person or animal with an infectious disease that is contagious.


Usage

A contagious disease is one that can be transmitted from one living being to another through direct or indirect contact. Thus the flu, which can be transmitted by coughing, and cholera, which is often acquired by drinking contaminated water, are contagious diseases. Although infectious is also used to refer to such diseases, it has a slightly different meaning in that it refers to diseases caused by infectious agents—agents such as viruses and bacteria that are not normally present in the body and can cause an infection. While the notion of contagiousness goes back to ancient times, the idea of infectious diseases is more modern, coming from the germ theory of disease, which was not proposed until the later nineteenth century. Contagious and infectious are also used to refer to people who have communicable diseases at a stage at which transmission to others is likely.

Related Words

Contagious, infectious are usually distinguished in technical medical use. Contagious, literally “communicable by contact,” describes a very easily transmitted disease as influenza or the common cold. Infectious refers to a disease involving a microorganism that can be transmitted from one person to another only by a specific kind of contact; venereal diseases are usually infectious. In nontechnical senses, contagious emphasizes the rapidity with which something spreads: Contagious laughter ran through the hall. Infectious suggests the pleasantly irresistible quality of something: Her infectious good humor made her a popular guest.

Other Word Forms

  • anticontagious adjective
  • anticontagiously adverb
  • anticontagiousness noun
  • contagiosity noun
  • contagiously adverb
  • contagiousness noun
  • noncontagious adjective
  • noncontagiously adverb
  • noncontagiousness noun
  • uncontagious adjective
  • uncontagiously adverb

Etymology

Origin of contagious

First recorded in 1350–1400; Middle English, from Late Latin contāgiōsus, from contāgi(ō) contagion + -ōsus -ous

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The contagious respiratory illness typically kills thousands of people in the U.S. each year, though that number can rise significantly in years with troublesome viral variants.

From The Wall Street Journal

“He had such a strong ‘I can’ belief in himself that was kind of contagious,” Meier said.

From The Wall Street Journal

A wave of the highly contagious respiratory syncytial virus is beginning to wash over the United States, sending greater numbers of babies and toddlers to the hospital for professional care.

From Los Angeles Times

Leprosy, he told them, is one of the least contagious of all infectious diseases; he’d never caught it himself.

From The Wall Street Journal

"He made me feel a million dollars. His enthusiasm and positivity was contagious."

From BBC