Stratospheric means extremely high or reaching incredible levels. When something goes stratospheric, it shoots way up beyond what anyone expected. A company's sales might go stratospheric after a popular video about their product goes viral. A basketball player's performance could be called stratospheric after scoring 50 points in a single game.

The word comes from the stratosphere, a layer of Earth's atmosphere that starts about 6 to 10 miles above the ground and extends up to about 30 miles high. That's higher than where most clouds and weather are found, and around the height where many jet airplanes fly.

People also use stratospheric to describe anything that reaches astonishing heights: stratospheric prices, stratospheric expectations, or stratospheric success. If your favorite author's new book debuts at number one and stays there for months, selling millions of copies, you might say it achieved stratospheric popularity. The word captures that sense of breaking through ordinary limits and soaring into a realm few people reach.