Sink

1. Plumbing fixture consisting of a water basin fixed to a wall or floor and with a drainpipe. We wash our dishes using a sink.
2. To descend to the bottom; submerge. If you can't swim you will sink.
3. To fall or drop to a lower level. The temperature sank ten degrees when the sun went down.
4. To deteriorate in quality or condition. The patient is sinking fast and might die soon.
5. To make an impression. The meaning finally sank in.