This nut is named for its most common country of origin.

It’s a Brazil nut! Brazil nuts are fairly unique among nuts one might commonly see in a grocery store. They are not a domesticated crop like most other nuts, and are mainly wild-harvested from the Amazon rainforest. Some have advocated this as a model of a sustainable economic activity in the rainforest, but other studies have noted that in areas where nuts are heavily harvested, the regeneration of the species is poor.