Putrefaction

The term sepsis as now used in clinical surgery no longer retains its original meaning as synonymous with “putrefaction,” but is employed to denote all conditions in which bacterial infection has taken place, and more particularly those in which pyogenic bacteria are present.

What's the difference between fermentation and putrefaction?

The fermentations which are most important in the tannery are, firstly, the ordinary putrefaction which attacks hides as well as other animal matter, and which is usually a complicated process carried on by many sorts of bacteria and other micro-organisms.