/ Dictionary / Index I infernal machine: Meaning and Definition of Find definitions for: infer'nal machine' Pronunciation: [key] a concealed or disguised explosive device intended to destroy life or property. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. infernal inferno Related Content Daily Word Quiz: acquiesce Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language