What does the word ferment mean?

Usage examples for ferment

  1. In the township of Dummer, the settlers boil the tops, and add hops to the liquor, which they ferment, and from which they obtain excellent beer. – Roughing it in the Bush by Susanna Moodie
  2. Constantinople was in a ferment. – Dreamers of the Ghetto by I. Zangwill
  3. Even yet the principle of Darwin is but a spreading ferment in many spheres of human thought in which it is destined to bring the same revolution that it has worked in the sciences of organic life. – The Story of the Mind by James Mark Baldwin