Resin refers to the trichomes that are used to create hash. It’s also a term that references the sticky residue that amasses on the inside of a bowl (or other marijuana paraphernalia) after smoking product in it again and again. Resin can be scraped from the inside of the piece to remove a clog – or alternatively smoked, but this is usually done as a last resort because it contains lower THC levels and impurities.
“Can’t believe that we resorted to smoking that resin. Talk about a harsh high.”