- the ancient Roman god of war and agriculture, identified with the Greek god Ares.
- the planet fourth in order from the sun, having a diameter of 4,222 miles (6,794 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.
- of or relating to any of various pigments used in painting that are artificially made from an iron oxide base: Mars color; Mars pigments.
- the Roman god of war, the father of Romulus and Remus
- the fourth planet from the sun, having a reddish-orange surface with numerous dark patches and two white polar caps. It has a thin atmosphere, mainly carbon dioxide, and low surface temperatures. Spacecraft encounters have revealed a history of volcanic activity and running surface water. The planet has two tiny satellites, Phobos and Deimos. Mean distance from sun: 228 million km; period of revolution around sun: 686.98 days; period of axial rotation: 24.6225 hours; diameter and mass: 53.2 and 10.7 per cent that of earth respectively
- the alchemical name for iron
