human immunodeficiency virus
noun [ S ] medical specialized uk/ˌhjuː.mən ɪm.jʊ.nəʊ.dɪˈfɪʃ.ən.si ˈvaɪə.rəs/ us/ˌhjuː.mən ɪm.jʊ.noʊ.dɪˈfɪʃ.ən.si ˈvaɪ.rəs/ (abbreviation HIV)
人体免疫缺损病毒，艾滋病病毒
the virus that causes AIDS (= a serious disease that destroys the body's ability to fight infection)