By the Ancient Philosophers, Air was regarded As an element; But modern Science has shown that it is essentially A Mixture of Oxygen and Nitrogen, with A Small Amount of Carbon dioxide, the Average Proportions Being, by volume: Oxygen.96 per cent.; Nitrogen.00 per cent.; Carbon dioxide.04 per cent. These Proportions are Subject To A very slight Variability. Air Also always contains some Vapor of Water.
2. Symbolically: Something Unsubstantial, Light, Or Volatile. Charm Ache with Air. He was Still all Air and Fire. (Macaulay). [Air and Fire Being the finer and quicker Elements As opposed To Earth and water]
9. Intelligence; information.
10. A Musical Idea, Or Motive, rhythmically developed In consecutive Single Tones, so As To Form A Symmetrical and balanced Whole, which may Be sung by A Single Voice To the Stanzas of A hymn Or song, Or Even To Plain Prose, Or played Upon an instrument; A melody; A tune; an aria. In harmonised chorals, psalmody, Part songs, etc, the Part which Bears the Tune Or melody In modern Harmony usually the Upper Part is sometimes called the Air.
14. The representation Or Reproduction of the Effect of the Atmospheric Medium Through which Every Object In Nature is viewed. Carriage; attitude; action; movement; As, the Head of that Portrait has A Good Air.
16. To Expose To the Air for the purpose of cooling, refreshing, Or purifying; To ventilate; As, To Air A Room. It were Good wisdom . . . That the Jail were aired. (Bacon) Were you But riding Forth To Air yourself. (Shak)
Air is much used adjectively Or As the First Part of A Compound Term. In most Cases it Might Be written indifferently, As A Separate limiting Word, Or As the First Element of the Compound Term, with Or Without the hyphen; As, Air bladder, Air-Bladder, Or airbladder; Air cell, Air-Cell, Or aircell; Air-pump, Or airpump. Air Balloon. See Balloon. Air Bath. An Apparatus for the Application of Air To the Body. An Arrangement for drying Substances In Air of any desired Temperature. Air castle. See Castle In the Air, Under Castle. Air Compressor, A Machine for compressing Air To Be used As A Motive Power. Air crossing, A Passage for Air In A Mine. Air Cushion, an Air-tight Cushion which can Be inflated; Also, A Device for arresting Motion Without Shock by confined Air. Air fountain, A contrivance for producing A Jet of Water by the Force of Compressed Air. Air Furnace, A Furnace which depends On A Natural Draft and not On Blast. Air Line, A Straight line; A Bee Line. Hence Air-Line,; As, Air-Line Road.
(Science: medicine) Air Lock Unsupported and Liable To Be turned Or taken In flank; As, the army had its Wing In the Air. To Take Air, To Be divulged; To Be made public. To Take the Air, To Go abroad; To Walk Or Ride out.
Origin: Oe. Air, eir, F. Air, L. Aer, Fr. Gr, Air, Mist, for, Fr. Root To Blow, Breathe, Probably Akin To E. Wind. In Sense 10 the French has taking A meaning Fr. It. Aria Atmosphere, Air, Fr. The Same Latin word; and In Senses 11, 12, 13 the French meaning is either Fr. L. Aria, Or due To Confusion with F. Aire, In an older Sense of Origin, Descent. Cf. Ary, Debonair, Malaria, Wind. A Succession of Notes forming A distinctive sequence; she was Humming an Air from Beethoven.