mascon

Short definition from Wiktionary

Noun

1. 1
   A region within a solid astronomical body that is of higher density than the surrounding material.
2. 2
   A lunar mare that has a greater density of rock than the surrounding area.
3. 3
   mass concentration
4. 4
   Synonym of Macon.

Proper noun

1. 1
   Synonym of Mâcon.