/ Dictionary / Index B boring mill: Meaning and Definition of Find definitions for: bor'ing mill" Pronunciation: [key] a machine for boring large holes in heavy work, having a table on which the work rotates while the hole is bored vertically. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. boring machine Boris Related Content Daily Word Quiz: paradox Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language