thermosphere

Definition

The layer of the Earth's atmosphere directly above the mesosphere and directly below the exosphere.

Etymology

From thermo- + -sphere.

Example Sentences

• "The mesosphere may be described as the earth's intermediate or middle atmosphere, which separates the thermosphere above from the ozonosphere (or stratosphere) below, both of which are responsible for absorption of most of the ultraviolet part of the solar radiation and preventing it from reaching the earth's surface."