Pronunciation: (märz),[key] —n. 1. the ancient Roman god of war and agriculture, identified with the Greek god Ares.
2. Astron.the planet fourth in order from the sun, having a diameter of 4222 miles (6794 km), a mean distance from the sun of 141.6 million miles (227.9 million km), a period of revolution of 686.95 days, and two moons. See table under planet (def. 1).
—adj. (often l.c.) of or pertaining to any of various pigments used in painting that are artificially made from an iron oxide base: Mars color; Mars pigments.