词根词缀：retro-, retr-

【来源及含义】Latin: back, backward, backwards; behind

【同源单词】arrear, regurgitant menstruation, retroact, retroaction, retroactive, retroactively

词根词缀：viru-, vir-

【来源及含义】Latin: poison

【相关词根词缀】 A cross reference of another word family that is related directly, or indirectly, with: "poison": toxico-; veno-.

【同源单词】adenovirus, alphavirus, arborvirus, arenite, avirulence, calicivirus