Latex (pl. latices) is an emulsion (stable dispersion) of polymer microparticles in water. Latices are found in nature, but synthetic latices are common as well.
In nature, latex is found as a milky fluid, which is present in 10% of all flowering plants (angiosperms) and in some mushrooms (especially species of Lactarius). It is a complex emulsion that coagulates on exposure to air, consisting of proteins, alkaloids, starches, sugars, oils, tannins, resins, and gums. It is usually exuded after tissue injury. In most plants, latex is white, but some have yellow, orange, or scarlet latex. Since the 17th century, latex has been used as a term for the fluid substance in plants, deriving from the Latin word for 'liquid'. It serves mainly as defense against herbivores and fungivores.