FROTH

[verb] - to (cause a liquid to) have or produce a lot of small bubbles which often rise to the surfaceThe waves frothed as they crashed onto the beach. [I]Shake the drink before serving it to froth it up. [M]If a person or animal froths at the mouth, a mass of small bubbles appears from their mouth as the result of a disease.Someone with rabies may froth at the mouth.(informal) If a person froths at the mouth, they are extremely angry.She was more than annoyed - she was almost frothing at the mouth.