If you're looking for a common noun to describe something related to Milwaukee, you could use terms like:
* City: This is the most general term.
* Metropolis: This implies a large and important city.
* Municipality: A more formal term for a city or town governed by a local authority.
* Urban center: This emphasizes Milwaukee's role as a hub of activity.
You could also use more specific nouns depending on what you're trying to describe, such as:
* Brewery: Milwaukee is known for its breweries.
* Museum: Milwaukee has several well-known museums.
* Lakefront: Milwaukee's location on Lake Michigan.
* Park: Milwaukee has many parks.
Let me know if you can give me more context, and I can help you find a more specific common noun.