Animal virus and Retrovirus

Animal virus noun - An animal pathogen that is a virus.

Retrovirus and animal virus are semantically related. In some cases you can replace term "Retrovirus" with "Animal virus", this terms are similar.

Retrovirus noun - 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.

Animal virus and retrovirus are semantically related. You can use "Animal virus" instead a noun "Retrovirus".