[机] 气垫

Air \Air\ ([^a]r), n. [OE. air, eir, F. air, L. a["e]r, fr. Gr.
'ah`r, air, mist, for 'a[digamma]hr, fr. root 'a[digamma] 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. {A["e]ry},
{Debonair}, {Malaria}, {Wind}.]
1. The fluid which we breathe, and which surrounds the earth;
the atmosphere. It is invisible, inodorous, insipid,
transparent, compressible, elastic, and ponderable.

Note: 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, 20.96 per cent.; nitrogen,
79.00 per cent.; carbon dioxide, 0.04 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.'' --Shak.

He was still all air and fire. [Air and fire being
the finer and quicker elements as opposed to earth and
water.] --Macaulay
.

3. A particular state of the atmosphere, as respects heat,
cold, moisture, etc., or as affecting the sensations; as,
a smoky air, a damp air, the morning air, etc.

4. Any a["e]riform body; a gas; as, oxygen was formerly
called vital air. [Obs.]

5. Air in motion; a light breeze; a gentle wind.

Let vernal airs through trembling osiers play.
--Pope.

6. Odoriferous or contaminated air.

7. That which surrounds and influences.

The keen, the wholesome air of poverty.
--Wordsworth.

8. Utterance abroad; publicity; vent.

You gave it air before me. --Dryden.

9. Intelligence; information. [Obs.] --Bacon.

10. (Mus.)
(a) 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.
(b) In harmonized 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.

11. The peculiar look, appearance, and bearing of a person;
mien; demeanor; as, the air of a youth; a heavy air; a
lofty air. ``His very air.'' --Shak.

12. Peculiar appearance; apparent character; semblance;
manner; style.

It was communicated with the air of a secret.
--Pope.

12. pl. An artificial or affected manner; show of pride or
vanity; haughtiness; as, it is said of a person, he puts
on airs. --Thackeray.

14. (Paint.)
(a) The representation or reproduction of the effect of
the atmospheric medium through which every object in
nature is viewed. --New Am. Cyc.
(b) Carriage; attitude; action; movement; as, the head of
that portrait has a good air. --Fairholt.

15. (Man.) The artificial motion or carriage of a horse.

Note: 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}.
(a) An apparatus for the application of air to the body.
(b) 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}, adj.; as, air-line road.

{Air lock} (Hydr. Engin.), an intermediate chamber between
the outer air and the compressed-air chamber of a
pneumatic caisson. --Knight.

{Air port} (Nav.), a scuttle or porthole in a ship to admit
air.

{Air spring}, a spring in which the elasticity of air is
utilized.

{Air thermometer}, a form of thermometer in which the
contraction and expansion of air is made to measure
changes of temperature.

{Air threads}, gossamer.

{Air trap}, a contrivance for shutting off foul air or gas
from drains, sewers, etc.; a stench trap.

{Air trunk}, a pipe or shaft for conducting foul or heated
air from a room.

{Air valve}, a valve to regulate the admission or egress of
air; esp. a valve which opens inwardly in a steam boiler
and allows air to enter.

{Air way}, a passage for a current of air; as the air way of
an air pump; an air way in a mine.

{In the air}.
(a) Prevalent without traceable origin or authority, as
rumors.
(b) Not in a fixed or stable position; unsettled.
(c) (Mil.) Unsupported and liable to be turned or taken
in flank; as, the army had its wing in the air.

{on the air}, currently transmitting; live; -- used of radio
and television broadcasts, to indicate that the images and
sounds being picked up by cameras and microphones are
being broadcast at the present moment.

Note: In call-in programs where individuals outside a radio
or television studio have telephoned into the station,
when their voice is being directly broadcast, the host
of the program commonly states ``You're on the air.''
as a warning that the conversation is not private.

{To take air}, to be divulged; to be made public.

{To take the air}, to go abroad; to walk or ride out.