Meaning

• A substance composed of a large collection of bubbles or their solidified remains.

  "He doesn't like so much foam in his beer."

• A substance formed by trapping pockets of gas in a liquid or solid.

  "A foam mat can soften a hard seat."

• (by extension) Sea foam; the sea.

  "He is in Europe, across the foam."

• Fury.

Meaning

• To form or emit foam.

• To spew saliva as foam, to foam at the mouth.