What is the meaning of the word "bath"?

Definitions:

a relatively large open container that you fill with water and use to wash the body noun
- As part of the renovations, I installed a new ceramic bath.
a room containing a bathtub or shower and usually a washbasin and toilet noun
- My housemates didn't like the fact that I spent over an hour in the bath every morning.
a vessel containing liquid into which something is immersed, as to process it, to maintain it at a constant temperature, or to lubricate it noun
- I soaked the etching in an acid bath to preserve it.
an ancient Hebrew liquid measure equal to about 10 gallons noun
- A bath is composed of six hin.
the process of soaking and washing one's body in a bathtub noun
- I have a long bath every Sunday evening.
to clean one's body by immersion into water verb
- Children should bath every day.