illegal website; underground website
Refers to websites that host or promote illegal activities, such as drug sales, child pornography, or suicide encouragement. Often used in news and legal contexts. Compare with 裏サイト, which can refer to unofficial or hidden school/company sites.
See also: 裏サイト
The police cracked down on an illegal website selling drugs.
There was an incident where people who met on a suicide-encouraging website attempted group suicide.
Compound of 闇 (yami, 'darkness; underground') and サイト (saito, 'website'). The term emerged in the early 2000s to describe websites involved in illegal activities, often contrasted with 裏サイト.