Latin for "sea," it is an area of basalt rock on the surface of the Moon created relatively recently by oozing lava. The plural form of mare is maria. It is thought that most maria formed as a result of impacts on the Moon; lava bled from cracks made in the Moon's surface and filled craters to form the dark "seas" visible from Earth. Maria are the youngest and most crater-free regions on the Moon's surface.
The dark areas of the Moon, which consist of basalt lava flows erupted into depressions (typically old large impact craters called "basins") a few tens to hundreds of millions of years after the impact event.
The low albedo plains covering the floors of several large basins and spreading over adjacent areas. The mare material is comprised primarily of basaltic lava flows, in contrast to the anorthosites in the highlands.
Relatively dark-colored, smooth areas on the lunar surface, representing ancient lava flows which filled in and depressed still more ancient craters of relatively large size. The mare lavas are denser than the lighter colored rocks which they overlie, and which surround them, and as a result, they depress the floors of the craters which they 'fill' even further than they would be depressed if they were not covered by the lava.
Latin word for "sea." Galileo thought the dark featureless areas on the Moon were bodies of water, even though the Moon is essentially devoid of liquid water. The term is still applied to the basalt-filled impact basins common on the face of the Moon visible from Earth.
121] To dream of seeing mares in pastures, denotes success in business and congenial companions. If the pasture is barren, it foretells poverty, but warm friends. For a young woman, this omens a happy marriage and beautiful children.  See Horse.