1. A reference to the region of the earth's atmosphere between the troposphere and mesosphere, from 10 kilometers (6 miles) to 50 kilometers (30 miles) above the earth's surface.

It has no clouds and is marked by gradual increases in temperature.

2. A descriptive term for very high or the highest level or position of something, or the greatest amount: "The excessively cold weather this spring probably will cause a decrease in agricultural products and so result in stratospheric food prices."
3. Referring to extremely high or the highest point or degree on a ranked scale: "Because of the increase in oil prices, gas prices have shot up stratospherically this week."