Hop, species of Humulus, a genus belonging to the nettle family. It contains two or three species of twining vines, with rough, palmately-lobed leaves and cone-like catkins, which, increasing much in size, are the so-called hops. The common hop is H. lupulus, which is native to both Europe and North America, and has long been cultivated for the hops that are used in the brewing of beer and in the manufacture of yeasts. For commercial use the hop is extensively cultivated, the handling of the crop consisting in removing the catkins and carefully drying them. The crop in the United States in 1910 amounted to 44,000,000 pounds, Oregon alone producing 18,000,000 pounds.