noun
letters-to-the-editor column; readers' section
A dedicated section in a newspaper or magazine where readers' letters, opinions, and feedback are published.
新聞の通信欄に投稿する。
I submit a letter to the newspaper's readers' column.
noun
space for correspondence; message area
A broader use for any designated space for written messages, such as in a form, bulletin board, or digital interface.
申込書の通信欄にメッセージを記入してください。
Please write your message in the correspondence space on the application form.