froth

Short definition from Wiktionary

Noun

1. 1
   Foam.
2. 2
   Unimportant or insubstantial talk, events, or actions; drivel.
3. 3
   The idle rich.
4. 4
   Highly speculative investment.

Verb

1. 1
   To create froth in (a liquid).
2. 2
   (of a liquid) To bubble.
3. 3
   To spit, vent, or eject, as froth.
4. 4
   (literally) To spew saliva as froth; (figuratively) to rage, vent one's anger.
5. 5
   To cover with froth.