verbs
be in an agitated or excited state
"The Middle East is fermenting"; "Her mind ferments"
is a type of (narrower)
be in an agitated emotional state
"The customer was seething with anger"
work up into agitation or excitement
"Islam is fermenting Africa"
is a type of (narrower)
arouse or excite feelings and passions
"The ostentatious way of living of the rich ignites the hatred of the poor"; "The refugees' fate stirred up compassion around the world"; "Wake old feelings of hatred"
cause to undergo fermentation
"We ferment the grapes for a very long time to achieve high alcohol content"; "The vintner worked the wine in big oak vats"
go sour or spoil
"The milk has soured"; "The wine worked"; "The cream has turned--we have to throw it out"