A mass of small bubbles formed on or in liquid, typically by agitation or fermentation. noun
The foam on top of the cappuccino was perfectly frothy.
As the waves crashed against the shore, they left a trail of foam behind.
A lightweight form of rubber or plastic made by solidifying a liquid foam. noun
The mattress is made from memory foam for extra comfort.
Foam insulation is used to improve energy efficiency in buildings.
To produce or form a mass of small bubbles; to froth. verb
The soap began to foam as she rubbed it between her hands.
The river foamed as it rushed over the rocks.
To become agitated and produce foam. verb
The angry dog began to foam at the mouth.
The chemical reaction caused the liquid to foam vigorously.