What is the meaning of seethe?

verb

• Be noisy with activity.
  • usage: "This office is buzzing with activity"
  • synonyms: hum, buzz
• Be in an agitated emotional state.
  • usage: "The customer was seething with anger"
  • synonyms: boil
• Foam as if boiling.
  • usage: "a seething liquid"
• Boil vigorously.
  • usage: "The liquid was seething"; "The water rolled"
  • synonyms: roll