Word: brummagem

From Dictionary.com: brummagem

brum⋅ma⋅gem
   /ˈbrʌmədʒəm/ Show Spelled Pronunciation [bruhm-uh-juhm] Show IPA Pronunciation
–adjective
1. showy but inferior and worthless.
–noun
2. a showy but inferior and worthless thing.

The origin relates to Birmingham, counterfeit coins, and the 17th century. The words “rogue” and “scalawag” come to mind.