Septic is 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 Cockney rhyming slang for American, coming from Septic tank = Yank A polynomial of degree seven (also called heptic, septemic or septimic)… (More on Septic)