Noun

1. Temporary structures used in the building of bridges and other arched structures in order to hold the item in place until the building is sufficiently far advanced to support itself.
2. Scaffolding, temporary framework serving to support and brace a structure under construction until it can stand alone.

   2003 Erik Larson The Devil in the White City p.236:

   • ... the woefully incomplete Ferris Wheel ... was a half-moon of steel encased in a skyscraper of wooden falsework. (Describing the first Ferris Wheel at Chicago's World's Columbian Exposition, 1893.)