/ Dictionary / Index M magnetotail: Meaning and Definition of Find definitions for: mag•ne•to•tail Pronunciation: (mag-nē'tu-tāl"), [key] — n. Astron. the narrow and elongated region of the magnetosphere of the earth or of another planet that extends in the direction away from the sun. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. magnetostriction magnetotaxis Related Content Daily Word Quiz: clairvoyant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language