1. (adj.)infernal hellish; fiendish; diabolical: an infernal plot.
2. infernal extremely troublesome, annoying, etc.; outrageous: an infernal nuisance.
3. infernal of, inhabiting, or befitting hell or the underworld.
Etymology: (1325–75; ME < LL infernālis < L infern(us) situated below, of the underworld)
Definition of 'Infernal'
Princeton's WordNet
1. (adj)infernal an inhabitant of Hell "his roar made the infernals quake"
2. (adj)infernal characteristic of or resembling Hell "infernal noise"; "infernal punishment"
3. (adj)demonic, diabolic, diabolical, fiendish, hellish, infernal, satanic, unholy extremely evil or cruel; expressive of cruelty or befitting hell "something demonic in him--something that could be cruel"; "fires lit up a diabolic scene"; "diabolical sorcerers under the influence of devils"; "a fiendish despot"; "hellish torture"; "infernal instruments of war"; "satanic cruelty"; "unholy grimaces"
4. (adj)blasted, blame, blamed, blessed, damn, damned, darned, deuced, goddam, goddamn, goddamned, infernal expletives used informally as intensifiers "he's a blasted idiot"; "it's a blamed shame"; "a blame cold winter"; "not a blessed dime"; "I'll be damned (or blessed or darned or goddamned) if I'll do any such thing"; "he's a damn (or goddam or goddamned) fool"; "a deuced idiot"; "an infernal nuisance"
5. (adj)infernal of or pertaining to or characteristic of a very uncontrolled and intense fire "infernal heat"
1. (adj)Infernal 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
2. (adj)Infernal 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
3. (noun)Infernal an inhabitant of the infernal regions; also, the place itself
Definitions of Infernal 
