a collection of minute bubbles formed on the surface of a liquid by agitation, fermentation, etc.

foam on a glass of beer.

the froth of perspiration, caused by great exertion, formed on the skin of a horse or other animal.

froth formed from saliva in the mouth, as in epilepsy and rabies.

a thick frothy substance, as shaving cream.

(in firefighting)

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.

the layer of bubbles so formed.

a dispersion of gas bubbles in a solid, as foam glass, foam rubber, polyfoam, or foamed metal.

Literary . the sea.

to form or gather foam; emit foam; froth.

to cause to foam.

to cover with foam; apply foam to

to foam a runway before an emergency landing.

to insulate with foam.

to make (plastic, metal, etc.) into a foam. ?

foam at the mouth

to be extremely or uncontrollably angry.

verb

become flat

noun

cream , fluff , froth , head , lather , scum , spray , spume , suds , surf , yeast

verb

aerate , boil , burble , effervesce , ferment , fizz , froth , gurgle , hiss , lather , seethe , simmer , sparkle , bubble , cream , spume , suds , yeast , blow up , boil over , bristle , burn , explode , flare up , fume , rage , frost , head , scud , scum , whip