13-Letter Words Containing: E,R,O,R,S

• accumulation of fluid in the pleural cavity (the space between the lungs and the walls of the chest) often resulting from disease of the heart or kidneys

• an instrument that indicates whether two periodic motions are synchronous (especially an instrument that enables a pilot to synchronize the propellers of a plane that has two or more engines)

• an antineoplastic drug used to treat Hodgkin's disease

• brain surgery on human patients intended to relieve severe and otherwise intractable mental or behavioral problems

• Any qualified majority, specified in advance of a vote, required for the vote to be passed

• a board having 64 squares of two alternating colors