Definition of typhus
- an infectious disease caused by rickettsiae, characterized by a purple rash, headaches, fever, and usually delirium, and historically a cause of high mortality during wars and famines. There are several forms, transmitted by vectors such as lice, ticks, mites, and rat fleas. Also called spotted fever.
mid 17th century: modern Latin, from Greek tuphos 'smoke, stupor', from tuphein 'to smoke'