Definition for word: Argon

An nontoxic gas that many window manufacturers use instead of air between panes of insulated glass. Argon has higher insulation value than air and won't degrade the low-e coating like air will.

Referrence from

Argon (pronounced /ˈɑrɡɒn/) is a chemical element represented by the symbol Ar. Argon has atomic number 18 and is the third element in group 18 of the periodic table (noble gases). Argon is the third most common gas in the Earth's atmosphere, at 0.93%, making it more common than carbon dioxide. The complete octet (eight electrons) in the outer atomic shell makes it stable and resistant to bonding with other elements. Its triple point temperature of 83.8058 K is a defining fixed point in the International Temperature Scale of 1990. The name "argon" is derived from the Greek word αργος meaning "inactive", a reference to the fact that the element undergoes almost no chemical reactions.

View this term in Wikipedia