Plumbing is all the water pipes hidden in a building's walls. New plumbing, the plumbing failed, a plumbing job.
Every waste pipe has a U-bend holding water in it, and that water is the seal that keeps sewer gas out of the house — which is why a drain that has dried out smells. The trade is named after lead, the metal pipes were once made of.
1nounplumbingThe water pipes of a building.
“The old house needed new plumbing because the pipes kept leaking.”
plumbing is a system.