contributor; contributing writer
Refers to a person who writes and submits articles, typically for a publication. More specific than 寄稿者, emphasizing a professional or regular role.
See also: 寄稿
He has been active for many years as a contributing writer for the newspaper.
The magazine is looking for contributors.
Compound of 寄稿 (contribution of an article) and 家 (suffix for a specialist or professional).