Sporadic /(-răd"ĭk)/

Spo·rad·ic

Sporadic

a.
  1. Occurring singly, or apart from other things of the same kind, or in scattered instances; separate; single; as, a sporadic fireball; a sporadic case of disease; a sporadic example of a flower.

Phrases & Compounds
Sporadic disease
a disease which occurs in single and scattered cases. See the Note under Endemic, a.