exosphere

Noun

the outermost atmospheric layer
the uppermost layer of a planet's atmosphere
an extremely thin atmosphere, as on Saturn's moon Dione

Origin / Etymology

From exo- + -sphere.

Scrabble Score: 21

exosphere is a valid Scrabble (US) TWL word
exosphere is a valid Scrabble Word in Merriam-Webster MW Dictionary
exosphere is a valid Scrabble Word in International Collins CSW Dictionary

Words With Friends Score: 21

exosphere is a valid Words With Friends word