a. A colorless, odorless, tasteless, gaseous mixture, mainly nitrogen (approximately 78 percent) and oxygen (approximately 21 percent) with lesser amounts of argon, carbon dioxide, hydrogen, neon, helium, and other gases.
b. This mixture with varying amounts of moisture and particulate matter, enveloping the earth; the atmosphere.
a. The sky; the firmament.
b. A giant void; nothingness: The money vanished into thin air.
3. An atmospheric movement; a breeze or wind.
4. Sports A height achieved by a jump or as part of an airborne maneuver, as in skateboarding or snowboarding: getting big air off the halfpipe; had big airs on every run down the course.
5. Aircraft: send troops to Europe by air.
a. Public utterance; vent: gave air to their grievances.
b. The medium of broadcast radio or television: "often ridiculed ... extremist groups on air" (Christian Science Monitor).
a. A manner of behaving that conveys an impression: a leader with an air of conviction.
b. A distinctive quality or appearance; an aura: The messy room had an air of desperation to it.
c. The general environment or condition, as in attitudes and ideas: growing impatience in the air.
d. airs Affected behavior; affectation: put on airs. See Synonyms at affectation.
a. A melody or tune, especially in the soprano or tenor range.
b. A solo with or without accompaniment.
9. Air conditioning.
10. Archaic Breath.
v. aired, air·ing, airs
1. To expose to the air in order to dry, cool, or freshen; ventilate.
2. To make known to others; express publicly: aired my complaints. See Synonyms at voice.
3. To broadcast on television or radio: "The ad was submitted to CBS ... which accepted and aired it" (New York).
To be broadcast on television or radio: "tidbits that will air on tonight's 6 o'clock news" (Terry Ann Knopf).
1. Of or relating to the air or the movement of air: an air tube.
2. Existing or living in the air; aerial.
3. Powered by compressed air: an air horn.
4. Containing or inflated by air.
5. Of or relating to aircraft or aeronautics.
6. Of or relating to the broadcast or transmission of radio or television signals.
7. Imaginary or unreal: "The guy had just hit it big ... after ten years of eating air sandwiches" (Jonathan Kellerman).
air one out
Football To throw a long pass.
in the air
Abroad; prevalent: Excitement was in the air.
up in the air
Not yet decided; uncertain.
[Partly from Middle English air, gas, atmosphere (from Old French, from Latin āēr, from Greek; see wer-1 in the Appendix of Indo-European roots) and partly from French air, nature, quality, place of origin (from Latin ager, place, field; see AGRICULTURE, and Latin ārea, open space, threshing floor; see AREA). N., sense 8, from French air, tune, from Italian aria; see ARIA.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2019 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.