/ Dictionary / Index T Tychonic system: Meaning and Definition of Find definitions for: Ty•chon'ic sys"tem Pronunciation: (tī-kon'ik), [key] — Astron. Astron. a model for planetary motion devised by Tycho Brahe in which the earth is stationary and at the center of the planetary system, the sun and moon revolve around the earth, and the other planets revolve around the sun. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. Tycho tycoon Related Content Daily Word Quiz: penchant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language