Definition of "foam" in English

noun

1. A substance composed of a large collection of bubbles or their solidified remains, especially:

2. A material formed by trapping pockets of gas in a liquid or solid.

   • A foam mat can soften a hard seat.

3. (figuratively, poetic) The sea.

   • He is in Europe, across the foam.

4. Fury, rage, ire.

5. (African-American Vernacular, in the plural) Sneakers.

verb

1. (intransitive) To form or emit foam.

2. (intransitive) To spew saliva as foam; to foam at the mouth.

3. (firefighting) To coat or cover with foam.

   • It used to be common practice to foam the runway prior to an emergency landing, in case a fuel-fed fire occurred.