noun which may take the genitive case particle 'no'
Describes a work that has not yet been published; often used for books, manuscripts, or research papers.
彼の未刊行の原稿が図書館で見つかった。
His unpublished manuscript was found in the library.
Compound of 未 (mi, 'not yet') + 刊行 (kankō, 'publication').