What does communicable mean?
"Communicable" describes something capable of being transmitted or passed from one party to another. Today it is used chiefly in medicine and public health, where a communicable disease is one that spreads between people or animals through direct contact, contaminated food or water, airborne droplets, or insect vectors. Tuberculosis, cholera, and influenza are classic examples. In this context the word has a deliberately neutral, technical register: officials speak of "communicable diseases" rather than the more emotive "catching" illnesses of everyday speech. The word also retains an older, broader sense — the capacity of ideas, emotions, or qualities to be communicated and shared — though this use is now largely confined to formal writing. Derived from the Latin communicare, meaning to share or make common, "communicable" belongs to the same family as "communicate", "community", and "common". Its antonym, "noncommunicable", is itself a familiar term in modern health discourse, describing conditions such as diabetes and heart disease that do not spread person to person. Understanding the word helps readers navigate public-health reporting with precision.
Capable of being transmitted from one person or organism to another, especially of a disease.
"Measles is among the most communicable diseases known to medicine."
This is by far the dominant sense today, used almost exclusively in formal medical and public-health contexts.
Capable of being communicated, imparted, or shared with others (of ideas, feelings, or qualities).
"She had a communicable warmth that put every visitor at ease."
An older and now much rarer sense, surviving mostly in literary or formal prose.
The same Latin root that gives us 'communicable' disease also gives us 'communication' — for centuries the word meant simply 'shareable', and only later took on its ominous medical sense.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of communicable
"Communicable" derives from the Latin verb communicare, meaning to share or make common, which itself comes from communis, meaning shared or belonging to all. The word entered English via French and Latin in the late Middle Ages or early modern period, originally denoting anything that could be imparted or shared — knowledge, qualities, or property. Its medical application, describing diseases transmissible between people, became firmly established as epidemiology developed from the seventeenth century onward. Cognates sharing the same root include "communicate", "communion", "community", and "common", all preserving the underlying idea of shared participation.
Related word forms
How communicable is actually used
In modern usage 'communicable' appears overwhelmingly in medical and public-health contexts, where it carries a neutral, clinical register; in everyday speech 'contagious' or 'infectious' are far more common. The older general sense — an idea or quality that can be conveyed — survives mainly in formal writing and is now rare.
Easily confused with communicable
'Contagious' refers strictly to disease spread by direct contact, while 'communicable' is broader, covering transmission by any means including air, water, or vectors.