standalone book (i.e. not part of an anthology, series, etc.); (book published as a) single volume
tankōbon; individual volume of a manga series
漫画が単行本化された。
The manga was released as a standalone volume.
お気に入りの単行本を本棚に並べた。
I lined up my favorite standalone books on the shelf.
雑誌連載の作品がついに単行本として発売された。
The serialized magazine work was finally released as a standalone book.