The way I’d describe it is that, compared to other milk alternatives, it is the has the most body.
ie, think of it being closer to full-fat milk than to non-fat milk. You’ll notice that the taste lingers in your mouth a bit longer. (body can refer to it lingering for various reasons, but in this case, I think it’s fat content, like in milk?)
Another one with a body you might like is rice milk.