From Old English 'rotian' (to decay), from Proto-Germanic *rutōną — the PIE root may connect decay to destruction.
To decay by the action of bacteria and fungi.
From Old English 'rotian' meaning 'to rot, decay,' from Proto-Germanic *rutōną, from PIE *rewd- (to tear out, to dig). The same root may underlie Latin 'rudus' (rubble, debris). Key roots: *rewd- (PIE: "to tear out, to dig").