Hello!

Great question

Usually osmosis is a term that refers specifically about  movement of water, without the aid of any other mechanism. 

Because aquaporins are membrane proteins that aid in the transport of water molecules,

technically it would be better classified as protein facilitated diffusion 

That being said, whether it should be considered osmosis or facilitated diffusion is not incredibly important;

as long as the underlying mechanism and the reason for the movement is understood.

Hope this helps! :)