noun
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
警察は違法な薬物を販売する闇サイトを摘発した。
The police cracked down on an illegal website selling drugs.
闇サイトで知り合
There was an incident where people who met on a suicide-encouraging website attempted group suicide.