latex

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The colorless or milky sap of certain plants, such as the poinsettia or milkweed, that coagulates on exposure to air.
• noun A polymer emulsion consisting of such sap obtained from rubber trees, used to manufacture various thin elastic products such as balloons, disposable gloves, and medical and contraceptive devices. Some people are allergic to this substance.
• noun A similar material made from polymers derived from petroleum; synthetic latex.
• noun Latex paint.

from The Century Dictionary.

• noun A milk-like liquid occurring in many plants in special vessels (called laticiferous, or sometimes cinenchymatous), and exuding when the plant is wounded.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Bot.) A milky or colored juice in certain plants in cavities (called latex cells or latex tubes). It contains the peculiar principles of the plants, whether aromatic, bitter, or acid, and in many instances yields caoutchouc upon coagulation. The lattex of the India rubber plant produces the rubber of commerce on coagulation.
• noun (Chem.) Any aqueous emulsion of finely divided rubber or plastic particles, especially such an emulsion used as a base for paint.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun The milky sap of several trees that coagulates on exposure to air; used to make rubber.
• noun An emulsion of rubber in water, used in adhesives and the like.
• noun uncountable Natural latex rubber, especially non-vulcanized rubber, such as is used in making latex gloves, latex condoms, and latex clothing.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a water-base paint that has a latex binder
• noun a milky exudate from certain plants that coagulates on exposure to air