lyme Definition

an acute inflammatory disease that is caused by a spirochete (Borrelia burgdorferi) transmitted by ticks (genus Ixodes and especially I. dammini), that is usually characterized initially by a spreading red annular erythematous skin lesion and by fatigue, fever, and chills, and that if left untreated may later manifest itself in joint pain, arthritis, and cardiac and neurological disorders —called also Lyme

a serious disease that is spread by the bite of a small insect (called a deer tick)