What does "newsgroup" mean?

A repository on a computer network where people can post messages, usually about a single subject.

Newsgroup

Common synonyms include: discussion board, discussion group, forum, news group, newsgroup based, newsgroup oriented.

/ˈnuzˌɡɹup/ noun

noun ·Rare ·Advanced level

Noun

1
A repository on a computer network where people can post messages, usually about a single subject.
"Some of the users are 'old timers'; they have been around in the newsgroup for several years[…]"
2
an area on a computer network, especially on the internet, devoted to the discussion of a specified topic wordnet

"Oops, I posted the message to the wrong newsgroup."

From news + group.