noun
large crowd; mass of people
Almost always used in the set phrase 黒山の人だかり, meaning a dense, dark-looking crowd of people. The image is of a black mountain of people.
事故現場には黒山の人だかりができていた。
A large crowd had gathered at the accident scene.
人だかり is a general word for a crowd or throng of people. 黒山 emphasizes the dense, dark mass of the crowd, and is almost always used in the phrase 黒山の人だかり.
Compound of 黒 (black) and 山 (mountain), from the image of a dense crowd looking like a dark mountain.