sewer

Etymology 1

From Middle English sewer, seuer, from Anglo-Norman sewere (“water-course”), from Old French sewiere (“overflow channel for a fishpond”), from Vulgar Latin *exaquāria (“drain for carrying water off”), from Latin ex (“out of, from”) + aquāria (“of or pertaining to waters”) or from a root *exaquāre.

noun

1. A pipe or system of pipes used to remove human waste and to provide drainage.
   One of the hidden glories of Victorian engineering is proper drains. Isolating a city’s effluent and shipping it away in underground sewers has probably saved more lives than any medical procedure except vaccination. 14 June 2014, “It's a gas”, in The Economist, volume 411, number 8891

verb

1. (transitive) To provide (a place) with a system of sewers.

Etymology 2

From Middle English seware, seuere, from Anglo-Norman asseour, from Old French asseoir (“find a seat for”), from Latin assidēre, present active participle of assideō (“attend to”), from ad (“to, towards, at”) + sedeō (“sit”).

noun

1. (now historical) A servant attending at a meal who is responsible for seating arrangements, serving dishes, etc.
   While the Saxon was plunged in these painful reflections, the door of their prison opened, and gave entrance to a sewer, holding his white rod of office. 1819, Walter Scott, Ivanhoe
   His nephew Charles, meanwhile, had grown up in the royal household, working as a sewer, or waiter. 2011, Thomas Penn, Winter King, Penguin, published 2012, page 287

Etymology 3

table sew + -er

noun

1. One who sews.
2. A small tortricid moth, the larva of which sews together the edges of a leaf using silk.
   the apple-leaf sewer, Ancylis nubeculana