slang To peruse or frequent an online community, such as a forum, message board, or comment section, without leaving a comment or post of one's own. I've been lurking on this site since the early 2000s, but recently I've felt motivated to contribute some of my own writing. There are a vocal minority on here who will shout down dissenting opinions, but I think most of the people lurking on our site are actually pretty tolerant and reasonable.

To move or hang about (some place) in a suspicious, sneaking, or slinking manner. I had this horrible feeling someone was lurking around outside our house, so I called the police. This is the second time this month I've seen that guy lurking around—does anyone know who he is?