Breadcrumb Home > Dictionary > Index M midnight sun: Meaning and Definition of Find definitions for: mid'night sun' Pronunciation: [key] the sun visible at midnight in mid-summer in arctic and antarctic regions. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. midnight midnoon ✖ Related Content Daily Word Quiz: musth Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language