foam

Noun

• a lightweight material in cellular form; made by introducing gas bubbles during manufacture

• a mass of small bubbles formed in or on a liquid
  • the beer had a thick head of foam
    

Verb

• become bubbly or frothy or foaming
  • The boiling soup was frothing
    
  • The river was foaming
    
  • Sparkling water
    

Related words

• Synonyms: 
  froth , fizz , effervesce , sparkle , form bubbles