n. A gentle boiling, or the internal motion of the constituent parts of a fluid.n. That which is capable of causing fermentation.n. Figuratively, commotion; heat; tumult; agitation: as, to put the passions in a ferment.To cause to boil gently; cause ebullition in.To cause fermentation in.Figuratively, to set in agitation; excite; arouse.To undergo fermentation.Figuratively, to be in agitation; be excited, as by violent emotions or passions, or great problems.n.