Resin may refer to the dark to light brown substance which is scraped off the surface of the trichomes of a cannabis plant. Further, it is widely used to describe the by-product that sticks by the sides of a bowl or other cannabis holding pieces after smoking the product over a period of time. Some people scrap the resin off their paraphernalia, roll it into balls and smoke. It consists of tar, ash, carbon, and less potent cannabinoids, and is considered unhealthy for smoking.
Merriam-Webster Online Dictionary
resin (noun)1.
a) any of various solid or semisolid amorphous fusible flammable natural organic substances that are usually transparent or translucent and yellowish to brown, are formed especially in plant secretions, are soluble in organic solvents (as ether) but not in water, are electrical nonconductors, and are used chiefly in varnishes, printing inks, plastics, and sizes and in medicine
b) - rosin
2.
a) any of a large class of synthetic products that have some of the physical properties of natural but are different chemically and are used chiefly in plastics - resins
b) any of various products made from a natural resin or a natural polymer
transitive verb
to treat with resin
sap, extract, concentrate, hash, rosin