Crossword Genius

Gaseous mixture of which earth's atmosphere is composed (3)

Ross

I believe the answer is:

air

(Other definitions for air that I've seen before include "A melody or attitude" , "Mixture of gases, especially oxygen" , "Ventilate a tune?" , "Atmosphere surrounding the earth" , "Song; ventilate" .)

I've seen this clue in The Telegraph.
Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.