Search Result for "retrovirus": 
Wordnet 3.0

NOUN (1)

1. any of a group of viruses that contain two single-strand linear RNA molecules per virion and reverse transcriptase (RNA to DNA); the virus transcribes its RNA into a cDNA provirus that is then incorporated into the host cell; 



WordNet (r) 3.0 (2006):

retrovirus
    n 1: any of a group of viruses that contain two single-strand
         linear RNA molecules per virion and reverse transcriptase
         (RNA to DNA); the virus transcribes its RNA into a cDNA
         provirus that is then incorporated into the host cell