underground website; unofficial site; shadow site
Often refers to a website that operates outside official channels, containing critical, leaked, or unverified information. Frequently associated with school-related gossip or corporate exposés. Compare with 闇サイト, which implies illegal or deeply hidden activities.
On that school's underground website, slanderous comments about teachers had been posted.
Whistleblowing took place on the company's unofficial site.
underground school website; unofficial school message board
Compound of 裏 (ura, 'back, hidden side') and サイト (saito, 'website'). The term emerged in the early 2000s with the rise of internet forums and unofficial school or corporate sites.