outer layer of gases around a planet or star
The Earth's atmosphere is comprised of many different gases.

fast-moving heavenly body with a solid head surrounded by a glowing cloud of gases that circles the sun
Halley's comet may have first been seen as far back as 240 B.C.

entirely; absolutely
David completely understood the directions for the assignment.

things that happen
After a series of events that went wrong, no one wanted to stay at the camp.

a piece of rock or other matter from space that produces a bright light as it travels through earth's atmosphere
The meteor shined brightly in the night sky.

the profusion of meteors observed when the earth passes through a meteor swarm
During a meteor shower, clusters of bright lights can be seen in the sky.

a stony or metallic mass of matter that has fallen to the earth's surface from outer space
meteorites, more commonly known as shooting stars, occur when a meteor burns up in the Earth’s atmosphere.

something that is not alive
The moving object was being controlled by Harry.

to go through; to move through
The mosquitoes cannot pass through the netting.

to move very quickly
He shot down the stairs when he heard the fire alarm go off.