a. Of or relating to a lower world of the dead.
b. Of or relating to hell: infernal punishments; infernal powers.
2. Fiendish; diabolical: infernal instruments of war.
3. Abominable; awful: the infernal racket of the jackhammers.
[Middle English, from Old French, from Late Latin īnfernālis, from īnfernus, hell, from Latin, lower, underground; see dher- in the Appendix of Indo-European roots.]
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