Definition of "resin"

A viscous hydrocarbon secretion of many plants, particularly coniferous trees.  examples

Any of various yellowish viscous liquids or soft solids of plant origin; used in lacquers, varnishes and many other applications; chemically they are mostly hydrocarbons, often polycyclic.  examples

Any synthetic compound of similar properties.  examples

(transitive) To apply resin to.  examples