communicable

Communicable is an adjective meaning capable of being communicated or transmitted from one entity to another. In general usage it can describe information, signals, or diseases. Etymology derives from the Latin communicabilis, meaning “to share, impart.”

In medicine, the term is most often used to describe diseases that can spread from one person to another, directly or indirectly. A communicable disease is transmitted through contact with an infected person, airborne droplets, bodily fluids, contaminated surfaces, food or water, or via vectors such as mosquitoes. Examples include influenza, measles, and malaria. Some communicable diseases spread quickly through casual contact or close proximity; others require a vector or environmental reservoir. The distinction between contagious and other forms of transmission is sometimes nuanced: contagious disease is a subset of communicable disease characterized by rapid person-to-person spread, whereas not all communicable diseases are primarily contagious in everyday speech.

Beyond health, communicable is also used in information theory and communications to describe something that can be conveyed from sender to receiver, such as a message, data, or signals.