clou

plural clous

1. Something which holds the greatest attention; the chief point of interest.

   But had he not refused her the wherewithal to remember him—the pearls she needed as the clou of her dear collection, the great relic among relics?

   1911, Max Beerbohm, Zuleika Dobson

   1 more example

   Partly because they were constructed of multiple shot-scenes and recorded exclusively in LS, their elaborate decors acquired an even more privileged role — as tableaux and clous of spectacle — much in the manner of late nineteenth-century French stage productions […]

   1994, Richard Abel, The Ciné Goes to Town: French Cinema, 1896-1914, page 70