The word "glass" can be traced back, past the Old English word glæs to the Proto-Indo-European word gel.
That word – which meant "to shine" – is also the root for the Irish word glas meaning "green" and the Welsh word glas meaning blue.
In fact, even the English words grey, blue, green and yellow all are tied back to the Old English word glær and the Latin word glaesum – both of which mean amber.
How odd that the name for a material that is probably best known for the ability to be truly colorless shares etymology with so many names for colors.
