A trapeze was a suspended horizontal bar on which trapeze acts were performed, often at a circus.
History and specifics
The trapeze act at a circus.
Roberta Lincoln once went on an undercover mission where her identity was a trapeze artist. (ST - The Eugenics Wars novel: The Rise and Fall of Khan Noonien Singh, Volume 2)
Rachel Lopez worked for several summers as a circus trapeze artist in the early 24th century. She learned acrobatics to get over an innate fear of heights. (TNG novel: Exiles)
In 2369, William T. Riker, Deanna Troi, Worf, Alexander Rozhenko, and Geordi La Forge watched acrobats on the trapeze at Bitinga's Traveling Wonderment Exposition on Beta Maradi VII. When Alexander marveled at the spectacle, Worf said that with proper training, anyone could do it. Riker didn't think Klingons were built for acrobatic stunts. (TNG comic: "The Rich and the Dead!")
During the spectacle, Q shrank Worf and Troi to insect-size and hid them in the clothing of Kartakkan Cannonball. As he was being shot out of his cannonball, Q restored the officers to full size, leaving them careening through the air. Worf managed to catch the trapeze bar with one arm and Troi's hand with the other, saving them both. (TNG comics: "Reductions & Deductions", "Hidden Agendas!")
When the crew of Deep Space 9 met Vic Fontaine for the first time he told them they looked like a trapeze act and told them to wear appropriate period attire the next time. (DS9 episode: "His Way")