communicable disease, transmissible disease, infectious disease: a disease (such as one caused by a bacterium, virus or prion) that can spread from person to person, from animal to animal, between nonhuman animals and people, or from the environment to nonhuman animals or people, by direct or indirect means (e.g. via an insect vector). Communicable is more commonly used for human diseases than for animal diseases

contagious disease: a disease that spreads from person to person, from animal to animal, or between nonhuman animals and people, by direct contact with the infected individual or their secretions

infective animal or person: an animal or person who is at a stage of an infection at which they are able to spread the infection to others

noncommunicable: a disease or condition that is not spread among animals or humans, such as diabetes

transmissible: capable of being spread either directly (e.g. via contact or air) or indirectly (e.g. via a vector)