/ Dictionary / Index M machine screw: Meaning and Definition of Find definitions for: machine' screw" Pronunciation: [key] a threaded fastener, either used with a nut or driven into a tapped hole, usually having a diameter of about in. (6.4 mm) or less and a slotted head for tightening by a screwdriver. Cf. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. machinery steel machine shop Related Content Daily Word Quiz: rustic Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language