septic

Etymology 1

From Ancient Greek σηπτικός (sēptikós, “characterized by putridity”), from σηπτός (sēptós), from σήπω (sḗpō).

adj

1. Of or pertaining to sepsis.
2. Causing sepsis or putrefaction.
3. Of or pertaining to sewage or the disposal of sewage.
   septic tank; septic system

noun

1. A substance that causes sepsis or putrefaction.
   1750, John Pringle, Further Experiments on Substances Resisting Putrefaction, in 1809, Charles Hutton, George Shaw, Richard Pearson (editors), The Philosophical Transactions of the Royal Society of London, Volume X: 1750—1755, page 86, But, in the prosecution of this subject, he had met with very few real septics; and found many substances, commonly accounted such, of a quite opposite nature.
2. A septic tank; a system for the disposal of sewage into a septic tank, a septic system.
   The question is whether there are any spatial differences in how septics impact water quality, and whether these spatial variations should be considered when regulating septic improvement or removal. 2008, Alexey Voinov, Systems Science and Modeling for Ecological Economics, page 244

Etymology 2

From Latin septem (“seven”).

noun

1. (mathematics) A mathematical object (function, curve, surface, etc.) of degree seven.
   Enriques states that it is possible to construct a family of septics with a singular curve of degree 7 and genus 4 having a triple point that degenerates to the above configuration[…]. 2002, Ingrid C. Bauer, Fabrizio Catanese, Roberto Pignatelli, “Canonical Rings of Surfaces Whose Canonical System has Base Points”, in Ingrid C. Bauer et al., editors, Complex Geometry: Collection of Papers Dedicated to Hans Grauert, page 66
   Now consider the two septics C = U⁷ᵢ₌₁Cᵢ, D = U⁷ᵢ₌₁Dᵢ and note that for i = 1,2,3,4,5,6 the lines Cᵢ and Dᵢ are parallel, so that the intersection of two septics S' consists of 6⁶ + 6 + 1 = 43 points and it is the singular set of a foliation of degree 6. 2003, Antonio Campillo, Santiago Encinas, “Two Dimensional Complete Ideals”, in Luchezar L. Avramov et al., editors, Commutative Algebra: Interactions with Algebraic Geometry: International Conference, page 71

adj

1. (mathematics) Of the seventh degree or order.

Etymology 3

Short form of Cockney rhyming slang septic tank (“Yank”).

noun

1. (UK, Australia, New Zealand, rhyming slang, derogatory) An American, a Yank.
   Typical septic. Can't understand why the rest of the world thinks he's a fuck-knuckle. 1998 April 21, Justin Downey, “Re: rachel is awful cute!”, alt.nuke.the.USA, aus.flame.usa, and alt.flame
   “Didn′t enjoy the septics,” he says jokingly about the Americans. 2011, Roger Rees, Out of Calamity: Stories of Trauma Survivors, unnumbered page
   “What′s the septics′ Achilles heel?” I said using the slang septic tank, meaning Yank. 2012, John Righten, The Benevolence of Rogues, page 97