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foam

[fohm]
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noun
  1. a collection of minute bubbles formed on the surface of a liquid by agitation, fermentation, etc.: foam on a glass of beer.
  2. the froth of perspiration, caused by great exertion, formed on the skin of a horse or other animal.
  3. froth formed from saliva in the mouth, as in epilepsy and rabies.
  4. a thick frothy substance, as shaving cream.
  5. (in firefighting)
    1. a chemically produced substance that smothers the flames on a burning liquid by forming a layer of minute, stable, heat-resistant bubbles on the liquid's surface.
    2. the layer of bubbles so formed.
  6. a dispersion of gas bubbles in a solid, as foam glass, foam rubber, polyfoam, or foamed metal.
  7. Literary. the sea.
verb (used without object)
  1. to form or gather foam; emit foam; froth.
verb (used with object)
  1. to cause to foam.
  2. to cover with foam; apply foam to: to foam a runway before an emergency landing.
  3. to insulate with foam.
  4. to make (plastic, metal, etc.) into a foam.
Idioms
  1. foam at the mouth, to be extremely or uncontrollably angry.

Origin of foam

before 900; Middle English fom, Old English fām; cognate with German Feim
Related formsfoam·a·ble, adjectivefoam·er, nounfoam·ing·ly, adverbfoam·less, adjectivefoam·like, adjectivede·foam, verb (used with object)un·foamed, adjectiveun·foam·ing, adjective

Synonyms for foam

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1. froth, spume, head, fizz; scum.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for foam

spray, froth, cream, lather, surf, head, yeast, fluff, spume, suds, scum, gurgle, aerate, burble, effervesce, sparkle, seethe, simmer, hiss, ferment

Examples from the Web for foam

Contemporary Examples of foam

Historical Examples of foam

British Dictionary definitions for foam

foam

noun
  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
    1. 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
    2. (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
verb
  1. to produce or cause to produce foam; froth
  2. (intr) to be very angry (esp in the phrase foam at the mouth)
Derived Formsfoamless, adjectivefoamlike, adjective

Word Origin for foam

Old English fām; related to Old High German feim, Latin spūma, Sanskrit phena
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for foam
n.

Old English fam "foam, saliva froth," from West Germanic *faimo- (cf. Old High German veim, German Feim), from PIE *(s)poi-mo-, a root with connotations of "foam, froth" (cf. Sanskrit phenah; Latin pumex "pumice," spuma "foam;" Old Church Slavonic pena "foam;" Lithuanian spaine "a streak of foam"). The rubber or plastic variety so called from 1937.

v.

Old English famgian "to foam," from the source of foam (n.). Related: Foamed; foaming.

Online Etymology Dictionary, © 2010 Douglas Harper
foam in Science

foam

[fōm]
  1. Small, frothy bubbles formed in or on the surface of a liquid, as from fermentation or shaking.
  2. A colloid in which particles of a gas are dispersed throughout a liquid. Compare aerosol emulsion.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.