Definition of standard atmosphere
1
: an arbitrary ideal set of atmospheric conditions (as used in calculations of aircraft performance)
specifically
: the international standard specifying a temperature of 15° C and 760 millimeters pressure at sea level with a vertical temperature gradient of −6.5° C per kilometer up to 11 kilometers altitude and uniform temperature of −56.5° C above that level
Test Your Vocabulary
Which Word Does Not Belong?
-
- Which of these words does not mean "nonsense"?

Test your vocabulary with our 10-question quiz!
TAKE THE QUIZ
A daily challenge for crossword fanatics.
TAKE THE QUIZLove words? Need even more definitions?
Merriam-Webster unabridged
Share standard atmosphere