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
lobar pneumonia: pneumonia affecting one or more lobes of the lung; commonly due to streptococcal infection
bilge keel: either of two lengthwise fins attached along the outside of a ship's bilge; reduces rolling