Septic's a word derived from the Greek Σήψις, meaning 'putrefaction'. Septic may refer to: a septic infection, cf. sepsis Septic system, form of home-based sewage disposal Septic's used by Britons as a derogatory term for Americans. It comes from the cockney rhyming slang -- Septic tank = Yank -- the idea being to indicate that which a septic tank might contain.… (More on Septic)