What is the mass ramble?

Yes, mass has mass. It is, therefore, matter. If mass did not have mass, then it is "something" with no mass. That would make it "non-matter" and perhaps it might be energy.

Large number of people

Mass and mass are the same thing.

Somerville MA currently does not have a mass transit system.

The atomic mass number is the mass of the isotope of an element (the sum of number of protons and number of neutrons).