word-forming element meaning "arterial," from Latinized form of Greek arteria "windpipe; artery" (see artery).

"small artery," by 1808, from Modern Latin arteriola, diminutive of arteria "an artery" (see artery).

late 14c., from Medieval Latin trachea (13c.), as in trachea arteria, from Late Latin trachia, from Greek trakheia, in trakheia arteria "windpipe," literally "rough artery" (so called from the rings of cartilage that form the trachea), from fem. of trakhys "rough," from PIE *dhre-gh-, suffixed form of root *dher- (1). See artery for connection with windpipe in Greek science. Related: Tracheal.

early 15c., "of or pertaining to an artery," from French artérial (Modern French artériel), from Latin arteria "an artery; the windpipe" (see artery). The meaning "resembling an artery system, having a main channel and many branches" is from 1831.

late 14c., "an arterial blood vessel," from Anglo-French arterie, Old French artaire (13c.; Modern French artère), and directly from Latin arteria, from Greek arteria "windpipe," also "an artery," as distinct from a vein; related to aeirein "to raise" (see aorta).

They were regarded by the ancients as air ducts because the arteries do not contain blood after death, and 14c.-16c. artery in English also could mean "trachea, windpipe." Medieval writers, based on Galen, generally took them as a separate blood system for the "vital spirits." The word is used in reference to artery-like systems of major rivers from 1805; of railways from 1844.

c. 1300, "invisible gases that surround the earth," from Old French air "atmosphere, breeze, weather" (12c.), from Latin aer "air, lower atmosphere, sky," from Greek aēr (genitive aeros) "mist, haze, clouds," later "atmosphere" (perhaps related to aenai "to blow, breathe"), which is of unknown origin. It is possibly from a PIE *awer- and thus related to aeirein "to raise" and arteria "windpipe, artery" (see aorta) on notion of "lifting, suspended, that which rises," but this has phonetic difficulties.

In Homer mostly "thick air, mist;" later "air" as one of the four elements. Words for "air" in Indo-European languages tend to be associated with wind, brightness, sky. In English, air replaced native lyft, luft (see loft (n.)). In old chemistry, air (with a qualifying adjective) was used of any gas.

To be in the air "in general awareness" is from 1875; up in the air "uncertain, doubtful" is from 1752. To build castles in the air "entertain visionary schemes that have no practical foundation" is from 1590s (in 17c. English had airmonger "one preoccupied with visionary projects"). Broadcasting sense (as in on the air, airplay) is by 1927. To give (someone) the air "dismiss" is from 1900. Air pollution is attested by 1870. Air guitar is by 1983. Air traffic controller is from 1956.