The Collaborative International Dictionary of English v.0.48:

Infernal \In*fer"nal\, a. [F. infernal, L. infernalis, fr.
   infernus that which lies beneath, the lower. See Inferior.]
   [1913 Webster]
   1. Of or pertaining to or suitable for the lower regions,
      inhabited, according to the ancients, by the dead;
      pertaining to Pluto's realm of the dead, the Tartarus of
      the ancients.
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            The Elysian fields, the infernal monarchy. --Garth.
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   2. Of or pertaining to, resembling, or inhabiting, hell;
      suitable for hell, or to the character of the inhabitants
      of hell; hellish; diabolical; as, infernal spirits, or
      conduct.
      [1913 Webster]

            The instruments or abettors in such infernal
            dealings.                             --Addison.
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   Infernal machine, a machine or apparatus maliciously
      designed to explode, and destroy life or property.

   Infernal stone (lapis infernalis), lunar caustic;
      formerly so called. The name was also applied to caustic
      potash.

   Syn: Tartarean; Stygian; hellish; devilish; diabolical;
        satanic; fiendish; malicious.
        [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Machine \Ma*chine"\ (m[.a]*sh[=e]n"), n. [F., fr. L. machina
   machine, engine, device, trick, Gr. mhchanh`, from mh^chos
   means, expedient. Cf. Mechanic.]
   1. In general, any combination of bodies so connected that
      their relative motions are constrained, and by means of
      which force and motion may be transmitted and modified, as
      a screw and its nut, or a lever arranged to turn about a
      fulcrum or a pulley about its pivot, etc.; especially, a
      construction, more or less complex, consisting of a
      combination of moving parts, or simple mechanical
      elements, as wheels, levers, cams, etc., with their
      supports and connecting framework, calculated to
      constitute a prime mover, or to receive force and motion
      from a prime mover or from another machine, and transmit,
      modify, and apply them to the production of some desired
      mechanical effect or work, as weaving by a loom, or the
      excitation of electricity by an electrical machine.
      [1913 Webster]

   Note: The term machine is most commonly applied to such
         pieces of mechanism as are used in the industrial arts,
         for mechanically shaping, dressing, and combining
         materials for various purposes, as in the manufacture
         of cloth, etc. Where the effect is chemical, or other
         than mechanical, the contrivance is usually denominated
         an apparatus or device, not a machine; as, a bleaching
         apparatus. Many large, powerful, or specially important
         pieces of mechanism are called engines; as, a steam
         engine, fire engine, graduating engine, etc. Although
         there is no well-settled distinction between the terms
         engine and machine among practical men, there is a
         tendency to restrict the application of the former to
         contrivances in which the operating part is not
         distinct from the motor.
         [1913 Webster]

   2. Any mechanical contrivance, as the wooden horse with which
      the Greeks entered Troy; a coach; a bicycle. --Dryden.
      --Southey. --Thackeray.
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   3. A person who acts mechanically or at the will of another.
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   4. A combination of persons acting together for a common
      purpose, with the agencies which they use; as, the social
      machine.
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            The whole machine of government ought not to bear
            upon the people with a weight so heavy and
            oppressive.                           --Landor.
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   5. A political organization arranged and controlled by one or
      more leaders for selfish, private or partisan ends; the
      Tammany machine. [Political Cant]
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   6. Supernatural agency in a poem, or a superhuman being
      introduced to perform some exploit. --Addison.
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   Elementary machine, a name sometimes given to one of the
      simple mechanical powers. See under Mechanical.

   Infernal machine. See under Infernal.

   Machine gun.See under Gun.

   Machine screw, a screw or bolt adapted for screwing into
      metal, in distinction from one which is designed
      especially to be screwed into wood.

   Machine shop, a workshop where machines are made, or where
      metal is shaped by cutting, filing, turning, etc.

   Machine tool, a machine for cutting or shaping wood, metal,
      etc., by means of a tool; especially, a machine, as a
      lathe, planer, drilling machine, etc., designed for a more
      or less general use in a machine shop, in distinction from
      a machine for producing a special article as in
      manufacturing.

   Machine twist, silken thread especially adapted for use in
      a sewing machine.

   Machine work, work done by a machine, in contradistinction
      to that done by hand labor.
      [1913 Webster]

WordNet (r) 3.0 (2006):

infernal machine
    n 1: a bomb that has a detonating mechanism that can be set to
         go off at a particular time [syn: time bomb, infernal
         machine]