ˈstrad.əˌsfi(ə)r, -iə noun
Etymology: French stratosphère, from New Latin stratum + -o- + French sphère sphere, from Latin sphaera — more at sphere
1. : an upper portion of the atmosphere above seven miles more or less depending on latitude, season, and weather in which temperature changes but little with altitude, clouds of water are rare, and there is practically no deep convection — called also isothermal region
2.
a. : a very high or the highest region on a graded scale
meat prices are in the stratosphere — Joseph & Stewart Alsop
the stratosphere of English society — New Yorker
b. : the top part of an object or region
a sooty stratosphere of struts and girders — Berton Roueché
the leafy stratosphere of the forest — Edmond Taylor
c. : a highly abstract or experimental field of endeavor
pressing their value analyses into a disembodied stratosphere of transcendental mathematics — A.L.Locke
stratosphere of modern art — D.C.Rich