BHO

This method of consumption has been around for at least a decade, but the advent of more advanced extraction methods have led to a flood of cannabis concentrates that have boosted dabbing’s popularity.

A dab usually refers to a dose of concentrate that is heated on a hot surface, usually a nail, and then inhaled. It doesn't sound so controversial in those terms, but “blasting dabs” has become a dividing point within the community both because of the intense high that it produces and for the image that it presents to outsiders.

(Leafly.com)