Definition of "foam" []

• A mass of bubbles of air or gas in a matrix of liquid film, especially an accumulation of fine, frothy bubbles formed in or on the surface of a liquid, as from agitation or fermentation. (noun)
• A thick chemical froth, such as shaving cream or a substance used to fight fires. (noun)
• Frothy saliva produced especially as a result of physical exertion or a pathological condition. (noun)
• The frothy sweat of a horse or other equine animal. (noun)
• The sea. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "The most general definition of foam is a substance that is formed by trapping many gas bubbles in a liquid."
• "I had not heard about this Kevlar-reinforced foam, is there a public web site where I can read about it?"
• "It costs as little as $US28 to assemble from an Army surplus shoulder bag and some foam from a hardware store, and you use cardboard to both measure out the foam and reinforce the loose compartments of the shoulder bag."