ATMOLOGY, at-mol'o-ji, _n._ the science of the phenomena of aqueous
vapour.--_n._ ATMOL'OGIST. [Gr. _atmos_, vapour, and _logia_,
discourse--_legein_, to speak.]
ATMOLYSIS, at-mol'i-sis, _n._ a method of separating a mixture of gases by
taking advantage of their different rates of passage through a porous
septum. [Gr. _atmos_, vapour, and _lysis_, loosing--_lyein_, to loose.]
ATMOMETER, at-mom'e-t[.e]r, _n._ an instrument for measuring the rate of
evaporation from a moist surface. [Gr. _atmos_, vapour, and METER.]
ATMOSPHERE, at'mo-sf[=e]r, _n._ the gaseous envelope that surrounds the
earth or any of the heavenly bodies: any gaseous medium: a conventional
unit of atmospheric pressure: (_fig._) any surrounding influence.--_adjs._
ATMOSPHER'IC, -AL, of or depending on the atmosphere.--_adv._
ATMOSPHER'ICALLY.--ATMOSPHERIC ENGINE, a variety of steam-engine in which
the steam is admitted only to the under side of the piston; ATMOSPHERIC
HAMMER, a hammer driven by means of compressed air; ATMOSPHERIC RAILWAY, a
railway where the motive-power is derived from the pressure of the
atmosphere acting on a piston working in an iron tube of uniform bore. [Gr.
_atmos_, air, _sphaira_, a sphere.]
ATOLL, a-tol', or at'ol, _n._ a coral island consisting of a circular belt
of coral enclosing a central lagoon. [A Malay word.]
ATOM, at'om, _n._ a particle of matter so small that it cannot be cut or
divided, the unit of matter; anything very small.--_adjs._ ATOM'IC, -AL,
pertaining to atoms.--_ns._ ATOMIC'ITY; ATOMIS[=A]'TION (_med._) the
reduction of liquids to the form of spray; AT'OMISM, the doctrine that
atoms arranged themselves into the universe: the atomic theory; AT'OMIST,
one who believes in atomism.--_adj._ ATOMIS'TIC.--_adv._
ATOMIST'ICALLY.--_n._ AT'OMY, an atom, or mote: (_Shak._) a pygmy.--ATOMIC
PHILOSOPHY, a system of philosophy enunciated by Democritus, which taught
that the ultimate constituents of all things are indivisible particles,
differing in form and in their relations to each other; ATOMIC THEORY, the
hypothesis that all chemical combinations take place between the ultimate
particles of bodies, uniting each atom to atom, or in proportions expressed
by some simple multiple of the number of atoms. [Gr. _atomos_--_a_, not,
_temnein_, _tamein_, to cut. See ATOM.]
ATOMY, at'om-i, _n._ (_Shak._) a skeleton, walking skeleton. [Formerly also
_atamy_ and _natomy_, for _anatomy_, mistakingly divided _an atomy_.]
ATONE, at-[=o]n', _adv._ (_Spens._) at one, at once, together. [M.E. also
_attone_, earlier _atoon_, _aton_, _at one_, _at on_.]
ATONE, at-[=o]n', _v.i._ to give satisfaction or make reparation (with
_for_): to make up for deficiencies: (_Shak._) to agree, be in
accordance.--_v.t._ to appease, to expiate: (_arch._) harmonise, or
reconcile.--_ns._ ATONE'MENT, the act of atoning; reconciliation:
expiation: reparation: esp. (_theol._) the reconciliation of God and man by
means of the incarnation and death of Christ; ATON'ER.--_adv._ ATON'INGLY.
[See ATONE, above.]
ATONY, at'on-i, _n._ want of tone or energy: debility: relaxation.--_adj._
AT'ONIC (_pros._), without tone: unaccented. [Gr. _atonia_--_a_, neg.,
_tonos_, tone, strength. See TONE.]