Contagious

capable of being transmitted by bodily contact with an infected person or object:
contagious diseases.
carrying or spreading a contagious disease.
tending to spread from person to person:
contagious laughter.
contemporary examples

this makes the third date a natural moment to fess up about any contagious diseases.
third-date confessions hannah seligson may 19, 2010

except maybe when that kid is wearing a bright orange shirt, gl-sses too big for his face, and a contagious smile.
lennon and maisy stella & more youtube musical prodigies (video) jake h-ller june 2, 2012

in researching the ill-strious dead, i was astonished to learn that napoleon had a rather unique view of contagious disease.
the coming bioattack stephan talty june 4, 2009

after all, these are contagious diseases and represent a substantial public health threat.
a maddening case of the measles in orthodox jewish brooklyn kent sepkowitz june 12, 2013

his p-ssion for the business was contagious, inspiring so many who had the privilege of knowing him.
hollywood mourns agent ed limato nicole laporte july 3, 2010

historical examples

his zeal was of that kind which is contagious and kindles responsive fire.
the gunpowder plot and lord mounteagle’s letter henry hawkes spink jr.

her humor was contagious and richling was ready to catch it.
dr. sevier george w. cable

there was universal exultation and a contagious delirium of returning loyalty.
a history of the inquisition of the middle ages; volume iii henry charles lea

i am not able to determine whether it is or is not contagious.
north american medical and surgical journal, vol. 2, no. 3, july, 1826 various

the armed invasion of the anabaptists was repelled, but their contagious madness spread.
the rise of the dutch republic, volume i.(of iii) 1555-66 john lothrop motley

adjective
(of a disease) capable of being p-ssed on by direct contact with a diseased individual or by handling clothing, etc, contaminated with the causative agent compare infectious
(of an organism) harbouring or spreading the causative agent of a transmissible disease
causing or likely to cause the same reaction or emotion in several people; catching; infectious: her laughter was contagious
adj.

late 14c., from old french contagieus (modern french contagieux), from late latin contagiosus, from latin contagio (see contact (n.)).

contagious con·ta·gious (kən-tā’jəs)
adj.

of or relating to contagion.

transmissible by direct or indirect contact; communicable.

capable of transmitting disease; carrying a disease.

con·ta’gious·ness n.
contagious
(kən-tā’jəs)

capable of being transmitted by direct or indirect contact, as an infectious disease.

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

our living language : 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.