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.]
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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.
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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.
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