The name Brazil comes from the brazilwood tree (which I’m sure I took pictures of but have so many tree photos in the Amazon). In Portuguese it is called pau brazil. The tree produces a deep red dye, highly valued in the European clothing industry and was the first commercially exploited product in Brazil.
The Brazil nut tree is a different tree only found in the Amazon. (Belem)
Ver O Peso market located in Belem has many things from the Amazon - some you know like brazil nuts and acai and many you don't. For more infö go to http://travelwellflysafe.com/2015/09/08/things-i-have-learned-in-brazil/