The process of undergoing an effervescent change, as by the action of yeast; in a wider sense (Physiol. Chem.), the transformation of an organic substance into new compounds by the action of a ferment, either formed or unorganized. It differs in kind according to the nature of the ferment which causes it.
- The anaerobic conversion of sugar to carbon dioxide and alcohol by yeast.
- Any of a group of chemical reactions induced by living or nonliving ferments that split complex organic compounds into relatively simple substances.
- Unrest; agitation.