1. decorative chains, garlands, or ornaments hung in loops or curves, especially as festive decoration
Usage: informal; often used in plural or as a mass noun
2. excessive or showy ornamentation; decorative embellishment that is overdone or superficial
Usage: informal; often pejorative

Examples

• The ballroom was covered in festoonery for the holiday party.
• Colorful festoonery hung from every doorway and window.
• The storefront's festoonery attracted shoppers during the Christmas season.
• She criticized the building's excessive festoonery as tacky and overdone.
• The wedding venue was decorated with elegant festoonery of white flowers and ribbons.