(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
a software program capable of reproducing itself and usually capable of causing great harm to files or other programs on the same computer; "a true virus cannot spread to another computer without human assistance"
a harmful or corrupting agency; "bigotry is a virus that must not be allowed to spread"; "the virus of jealousy is latent in everyone"
a hemoprotein composed of globin and heme that gives red blood cells their characteristic color; function primarily to transport oxygen from the lungs to the body tissues; "fish have simpler hemoglobin than mammals"
any of a large variety of proteins normally present in the body or produced in response to an antigen which it neutralizes, thus producing an immune response