게시물이 · 게시물을
post (online), posting, notice
Example
그 게시물에 댓글이 많이 달렸어요.
That post got a lot of comments.
Word parts
게 put up+시 show+물 thing
Literally 'thing put up to show', like a notice on a board.
Good to know
In casual speech people often just say 글 or 게시글 for an online post.
Related words