A comprehensive dictionary of Japanese slang from the Meiji through Heisei eras, covering approximately 6,300 vulgarisms, secret terms, popular expressions, discriminatory terms, occupational jargon, youth slang, and other forms of colloquial language. Drawing on more than 1,000 diverse historical sources, it includes over 12,000 examples of usage and provides a systematic and comprehensive account of the origins, meanings, and usage of Japanese slang.