Mons Esam is a small, isolated mountain in the northern part of the Mare Tranquillitatis. It is located to the southeast of the crater Vitruvius, and to the west-northwest of Lyell. To the northeast of this ridge is the bay called Sinus Amoris. The selenographic coordinate of this feature is 14.6° N, 35.7° E, and it has a maximum diameter at the base of 8 km. (wikipedia entry)
A mons is a mountain. On the Moon they are named after terrestrial mountain ranges, nearby craters, and deceased scientists who have made outstanding or fundamental contributions to their fields.