contagious

adjective con·ta·gious \ kən-ˈtā-jəs \
Updated on: 20 May 2018

Definition of contagious

1 : transmissible by direct or indirect contact with an infected person
  • contagious diseases
2 : bearing contagion
  • contagious people
3 : used for contagious diseases
  • a contagious ward
4 : exciting similar emotions or conduct in others
  • contagious enthusiasm
  • contagious laughter

contagiously

adverb

contagiousness

noun

Examples of contagious in a Sentence

  1. It's a highly contagious virus.

  2. I have a cold and I'm still contagious.

  3. I'm sick, but the doctor says I'm not contagious.

Recent Examples of contagious from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'contagious.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

What is the Difference Between contagious and infectious?

The words contagious and infectious can be confusing because they do not designate wholly distinct categories; something is not either contagious or infectious.

Essentially, infectious diseases and contagious diseases are caused by disease-producing agents such as bacteria and viruses, but they differ in that contagious diseases can be spread to other people by direct or indirect contact.

Anything contagious, such as the flu, is always automatically infectious: if you can catch it from someone, it's being passed to you via an infectious agent, which is the thing that gets you sick—usually a virus or a bacteria.

The reverse, however, isn't true. Just because something is infectious does not mean it's contagious. Food poisoning, for example, is infectious but not contagious: food can be contaminated with a bacteria (an infectious agent) that makes you sick, but you can't give your food poisoning to someone else by shaking their hand or even giving them a kiss.

Both contagious and infectious are also used figuratively, often in much happier contexts: laughter can be contagious; someone's enthusiasm can be infectious. While both words are used figuratively of both pleasant and unpleasant things, contagious is more often chosen for the unpleasant, as when it's grumpiness or fear that seems to be spreading.

Origin and Etymology of contagious

contagious Synonyms


CONTAGIOUS Defined for English Language Learners

contagious

Definition of contagious for English Language Learners

  • : able to be passed from one person or animal to another by touching

  • : having a sickness that can be passed to someone else by touching

  • : capable of being easily spread to others : causing other people to feel or act a similar way


CONTAGIOUS Defined for Kids

contagious

adjective con·ta·gious \ kən-ˈtā-jəs \

Definition of contagious for Students

1 : able to be passed from one individual to another through contact
  • a contagious disease
2 : having a sickness that can be passed to someone else
3 : causing other people to feel or act a similar way
  • a contagious laugh

Medical Dictionary

contagious

adjective con·ta·gious \ -jəs \

medical Definition of contagious

1 : communicable by contact
  • tuberculosis in the contagious stage
— compare infectious 2
2 : bearing contagion
  • many persons…are contagious long before they are aware of the presence of their disease
  • Journal of the American Medical Association
3 : used for contagious diseases
  • a contagious ward

contagiously

adverb

contagiousness

noun


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