tumor virus: a cell-free filtrate held to be a virus responsible for a specific neoplasm
virus: (virology) ultramicroscopic infectious agent that replicates itself only within cells of living hosts; many are pathogenic; a piece of nucleic acid (DNA or RNA) wrapped in a thin coat of protein
marseilles fever: a disease (common in India and around the Mediterranean area) caused by a rickettsia that is transmitted to humans by a reddish brown tick (ixodid) that lives on dogs and other mammals