|1.||a mass of small bubbles of gas formed on the surface of a liquid, such as the froth produced by agitating a solution of soap or detergent in water|
|2.||frothy saliva sometimes formed in and expelled from the mouth, as in rabies|
|3.||the frothy sweat of a horse or similar animal|
|4.||a. any of a number of light cellular solids made by creating bubbles of gas in the liquid material and solidifying it: used as insulators and in packaging|
|b. (as modifier): foam rubber; foam plastic|
|5.||a colloid consisting of a gas suspended in a liquid|
|6.||a mixture of chemicals sprayed from a fire extinguisher onto a burning substance to create a stable layer of bubbles which smothers the flames|
|7.||a poetic word for the sea|
|8.||to produce or cause to produce foam; froth|
|9.||(intr) to be very angry (esp in the phrase foam at the mouth)|
|[Old English fām; related to Old High German feim, Latin spūma, Sanskrit phena]|
(Hos. 10:7), the rendering of _ketseph_, which properly means twigs or splinters (as rendered in the LXX. and marg. R.V.). The expression in Hosea may therefore be read, "as a chip on the face of the water," denoting the helplessness of the piece of wood as compared with the irresistable current.
in physical chemistry, a colloidal system (i.e., a dispersion of particles in a continuous medium) in which the particles are gas bubbles and the medium is a liquid. The term also is applied to material in a lightweight cellular spongy or rigid form. Liquid foams are sometimes made relatively long-lasting-e.g., for fire fighting-by adding some substance, called a stabilizer, that prevents or retards the coalescence of the gas bubbles. Of the great variety of substances that act as foam stabilizers, the best known are soaps, detergents, and proteins. Proteins, because they are edible, find wide use as foaming agents in foodstuffs such as whipped cream, marshmallow (made from gelatin and sugar), and meringue (from egg white). The foam used to combat oil fires consists of bubbles of carbon dioxide (liberated from sodium bicarbonate and aluminum sulfate) stabilized by dried blood, glue, or other cheap protein-containing materials. Beer foam is believed to be stabilized by the colloidal constituents present, which include proteins and carbohydrates. Foaming may be undesirable, as in lubricating oils, and its prevention is not always easy. Aqueous foams usually can be broken by treatment with small amounts of certain alcohols.
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