/ Dictionary / Index A aurora borealis: Meaning and Definition of Find definitions for: auro'ra bo•re•al'is Pronunciation: (bôr"ē-al'is, -ā'lis, bōr"-), [key] — Meteorol. Meteorol. the aurora of the Northern Hemisphere. Also called Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. aurora australis auroral Related Content Daily Word Quiz: nonchalant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language