What is the meaning of ferment?

noun

• A state of agitation or turbulent change or development.
  • usage: "the political ferment produced new leadership"; "social unrest"
  • synonyms: agitation, fermentation, tempestuousness, unrest
• A substance capable of bringing about fermentation.
• A process in which an agent causes an organic substance to break down into simpler substances; especially, the anaerobic breakdown of sugar into alcohol.
  • synonyms: zymosis, zymolysis, fermentation, fermenting

verb

• Be in an agitated or excited state.
  • usage: "The Middle East is fermenting"; "Her mind ferments"
• Work up into agitation or excitement.
  • usage: "Islam is fermenting Africa"
• Cause to undergo fermentation.
  • usage: "We ferment the grapes for a very long time to achieve high alcohol content"; "The vintner worked the wine in big oak vats"
  • synonyms: work
• Go sour or spoil.
  • usage: "The milk has soured"; "The wine worked"; "The cream has turned-we have to throw it out"
  • synonyms: sour, turn, work