Board Thread:General Discussion/@comment-9732657-20130519011726/@comment-6963992-20130621124736

Stefan (Shikai - "Rust & Shatter") wrote: Omniguy183 wrote: ^He even called White a hollow based off of a shinigami's soul. Which means he's a hollow.

I believe Aizen waited until he had the finished 'product' before naming it Arrancar; so all experimental samples preceding it were simply referred to as Hollows.

Kaname said that White was completely different from all the types of Hollows they had created so far; being the first one created based on the soul of a Shinigami.

Kaname also said that White didn't just undergo Hollowfication, but it actually managed to achieve its final form; which indicates that White was something 'more' than just a Hollow. No Arrancar's tear off their masks to gain shinigami powers and the hogyoku is how Aizen created his Arrancar's. The Hogyoku was not involved in white and as such his isn't an Arrancar. Also,arrancar's already existed and if Kaname meant becoming an Arrancar he would have said it.