infectious

Adjective

Positive
infectious

Comparative
more infectious

Superlative
most infectious

(pathology) If a disease is infectious, it is can be spread between organisms through the environment.
Infectious diseases like cholera are far less deadly today than they used to be.
(pathology) If a person, plant, or animal is infectious, they can spread disease to others.
You can still be infectious even after you feel better.
If a feeling or idea is infectious, it spreads easily to other people.
She had an infectious laugh, and everyone loved her.