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Meaning of Mare Tyrrhenum

Ma're Tyr•rhe'num

Pronunciation: (ti-rē'num), [key]
  1. (Tyrrhenian Sea) an area in the southern hemisphere of Mars, appearing as a dark region when viewed telescopically from the earth.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.