病毒学 bìngdúxué virology Origin Definitions Defs Strokes Stroke Words Sentences Sents 病毒 bìngdú noun virus a type of tiny microorganism that causes infection and can only reproduce inside the living cells of a host学 學 xué nounaffix branch of learning (bound form) a subject or branch of study; often used as a suffix for -logy, -ics, or -science