Webster's Revised Unabridged Dictionary · 1913

Infernal

Infernal , adjective

[French infernal, Latin infernalis, from infernus that which lies beneath, the lower. See Inferior.]

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.
The Elysian fields, the infernal monarchy. — Garth
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.
The instruments or abettors in such infernal dealings. — Addison
Collocations (2)
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.

Infernal , noun

An inhabitant of the infernal regions; also, the place itself. [Obsolete] — Drayton