Can we call HIV onkovirus?

Oncovirus is a term referring to a virus, that causes cancer. Now HIV is a virus. Like all viruses it wants to go into a cell and it wants make the cell make more viruses. Virus and cancer intersect when a virus replicates in a manner that involves messing with the hosts DNA so that it now transcribes both normal features and Virus parts.

Cancer is the unchecked proliferation of cells resulting in the formation of tumors. Cancer happens when the virus changing the DNA alters the genes in such a way that a checkpoint has been ruined or a gene that is involved with reproduction or something that controls reproduction (something involved with cell signals or with reading DNA or releasing a material meant to stop reproduction) is messed with.

So while, yes HIV does insert itself all up into it's host DNA, (it's a retrovirus) it doens't usually mess with the areas that involve the previously mentioned genes (the ones involved in the reproduction process). So while the mechanism of DNA insertion is still at work, the particular areas targeted don't allow this virus to specifically cause cancer.