A Glass

1. (uncountable) An amorphous solid, often transparent substance made by melting sand with a mixture of soda, potash and lime.
2. (countable) A vessel from which one drinks, especially one made of glass, plastic, or similar translucent or semi-translucent material.
3. (metonymically) The quantity of liquid contained in such a vessel.
4. (uncountable) Glassware.
5. A mirror.
6. A magnifying glass or telescope.
7. (sports) A barrier made of solid, transparent material.
   1. (basketball, colloquial) The backboard.
   2. (ice hockey) The clear, protective screen surrounding a hockey rink.
8. A barometer.
9. (attributive, in names of species) Transparent or translucent.
10. (obsolete) An hourglass.
11. (uncountable, photography, informal) Lenses, considered collectively