Breadcrumb Home > Dictionary > Index J junk DNA: Meaning and Definition of Find definitions for: junk DNA Pronunciation: [key] segments of DNA that have no apparent genetic function. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. junk call junker ✖ Related Content Daily Word Quiz: hortatory Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language