Definition of "Ferment" :
noun: a process in which an agent causes an organic substance to break down into simpler substances; especially, the anaerobic breakdown of sugar into alcohol
noun: a state of agitation or turbulent change or development
"The political ferment produced new leadership."
noun: a substance capable of bringing about fermentation
verb: go sour or spoil
verb: cause to undergo fermentation
"We ferment the grapes for a very long time to achieve high alcohol content."
verb: work up into agitation or excitement
"This religion is fermenting Africa."
verb: be in an agitated or excited state
"The Middle East is fermenting."