sporadic

SPORADIC, SPORADICAL, a. [Gr., separate, scattered; whence certain isles of Greece were called Sporades.] Separate; single; scattered; used only in reference to diseases. A sporadic disease, is one which occurs in particular persons and places, in distinction from an epidemic, which affects persons generally or in great numbers.

Sporadic diseases are opposed to epidemics, as accidental, scattered complaints, neither general nor contagious.