legionnaires' disease: acute (sometimes fatal) lobar pneumonia caused by bacteria of a kind first recognized after an outbreak of the disease at an American Legion convention in Philadelphia in 1976; characterized by fever and muscle and chest pain and headache and chills and a dry cough
entity: that which is perceived or known or inferred to have its own distinct existence (living or nonliving)
clonus: convulsion characterized by alternating contractions and relaxations