Yakuza (Japanese: ヤクザ, [jaꜜkɯza]), also known as gokudō (極道, "the extreme path", [gokɯdoː]), are members of transnational organized crime syndicates originating in Japan. The Japanese police, and media by request of the police, call them bōryokudan (暴力団, "violent groups", [boːɾʲokɯdaɴ]), while the yakuza call themselves "ninkyō dantai" (任侠団体 or 仁侠団体, "chivalrous organizations", [ɲiŋkʲoː daɴtai]). The yakuza are notorious for their strict codes of conduct and their organized fiefdom-nature. They have a large presence in the Japanese media and operate internationally with an estimated 102,000 members.
From Japanese やくざ (yakuza). See there for more details.
yakuza (plural yakuza)
From Latin triad-, stem of trias (“three, triad”), from Ancient Greek τριάς (triás); applied by British authorities to underground society in Hong Kong based on geometry of Chinese character.
triad (plural triads)