water glass

water glass (countable and uncountable, plural water glasses)

1. (inorganic chemistry) Any of various water-soluble silicate compounds, especially when occurring in dissolved, jelly-like form.
   • 1993, John Banville, Ghosts

     No; what I felt was a sort of glazed numbness, as if I were suspended in some thin, transparent stuff, like one of the eggs my mother used to preserve in waterglass when I was a child.

2. A water gauge for a steam boiler.
3. An instrument consisting of an open box or tube with a glass bottom, used for examining objects in the water, as upon the sea bottom in shallow places.

• liquid glass
• sodium silicate
• soluble glass

• glass water