sink

noun

1
a covered cistern; waste water and sewage flow into it
2
plumbing fixture consisting of a water basin fixed to a wall or floor and having a drainpipe
3
a depression in the ground communicating with a subterranean passage (especially in limestone) and formed by solution or by collapse of a cavern roof
4
(technology) a process that acts to absorb or remove energy or a substance from a system
the ocean is a sink for carbon dioxide

1
fall heavily or suddenly; decline markedly
The real estate market fell off
2
embed deeply
She sank her fingers into the soft sand
He buried his head in her lap
3
descend into or as if into some soft substance or place
He sank into bed
She subsided into the chair
4
pass into a specified state or condition
He sank into nirvana
5
fall or descend to a lower place or level
He sank to his knees
6
cause to sink
The Japanese sank American ships in Pearl Harbor
7
fall or sink heavily
He slumped onto the couch
My spirits sank
8
go under, "The raft sank and its occupants drowned"

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