where did the term 5th wheel come from
Fifth-wheel coupling The term fifth wheel comes from a similar coupling used on four-wheel horse-drawn carriages and wagons. The device allowed the front axle assembly to pivot in the horizontal plane, to facilitate turning. Basically a wheel was placed on the rear frame section of the truck, which back then only had four wheels; this wheel that was placed on the frame was the "fifth wheel", hence the name. The trailer needed to be raised so that the trailer's pin would be able to drop into the central hole of the fifth wheel.
Fifth Harmony Fifth Harmony is an American girl group based in Miami, composed of Ally Brooke, Normani Kordei, Dinah Jane, Lauren Jauregui, and previously Camila Cabello until her departure from the group on December 18, 2016.[2][3] The group signed a joint record deal with Simon Cowell's label Syco Records and L.A. Reid's label Epic Records after forming and finishing third in the second season of the American televised singing competition The X Factor in 2012. Rising to prominence by social media, the group's debut extended play and their three studio albums all charted within the top ten of the Billboard 200 in the United States.