Organic substance that forms a plastic material following polymerization initiated by heat or chemical activation. It is usually transparent or translucent, not water soluble, and named according to chemical composition, physical structure, or means of activation or curing.

Hardened exudate from wounded stem or leaves that is soluble in alcohol but not in water.

A natural or prepared product, either solid or semi-solid in nature. Natural resins are exudations from trees, such as mastic; prepared resins are oleoresins from which essential oil has been removed.

These are wax-containing plant oils, often secreted to fill in injured tissues, much like a blood clot, sometimes used to protect leaves from loss of water through evaporation or to render them unpalatable.

Amorphous brittle substance resulting from a plant secretion.

A sticky sap or liquid which comes from some types of tree.

An amorphous, nonvolatile solid or soft-solid substance, which is a natural exudation from plants. It is practically insoluble in water but dissolves in alcohol.

An exudation from certain trees which becomes solid or semisolid on exposure to air (e.g. mastic).