sink
sink is a valid 4-letter word worth 8 points in Scrabble and 9 points in Words with Friends.
What does sink mean?
Fall heavily or suddenly; decline markedly.
Descend into or as if into some soft substance or place.
Cause to sink.
Appear to move downward.
Fall or descend to a lower place or level.
Go under.
Pass into a specified state or condition.
Fall or sink heavily.
Embed deeply.
Plumbing fixture consisting of a water basin fixed to a wall or floor and having a drainpipe.
(technology) a process that acts to absorb or remove energy or a substance from a system.
“the ocean is a sink for carbon dioxide”
A depression in the ground communicating with a subterranean passage (especially in limestone) and formed by solution or by collapse of a cavern roof.
A covered cistern; waste water and sewage flow into it.