I would say business casual.
MB attracts a diverse crowd. 30-something to 70-something. The over 50"s group tend to "dress up" for a "special dinner" (like in their hay day), younger customers, dress business casual, country casual, and {even} jeans. NO T-SHIRTS though. Even in trendy (SOHO NYC) eateries, less folks dress-to-impress, and more folks dress up to their level of personal comfort! Hope this is helpful.
Dress is casual
Definitely casual. My table was wearing riding gear, the next table were two older ladies who looked as though they had been gardening.
Casual
Casual wear.
It's a mix, casual to fairly dressy attire. The bar on the first floor is far more casual than the upstairs dining area.
Almost anything goes. Downstairs and bar are more casual. Upstairs, a little more dressy.
I saw a mixture, when I visited last. There was a wedding upstairs so they were in formal attire, we were in morotcycle riding gear.
Casual to business casual. People look comfortable.
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