A tankōbon (単行本, "independent/standalone book") is the Japanese term for a book that is complete in itself and is not part of a series or corpus (similar to a monograph), though in modern Japan it is most often used in reference to individual volumes of a single manga, as opposed to magazines (雑誌 zasshi), which feature multiple series. It can be used for a novel, a nonfiction work, an economics textbook, a book of beauty tips, a book presenting a coherent set of photographs, an exhibition catalogue that samples earlier books, and so forth in a hardcover format. It is more specific than plain hon, which encompasses such books but also one or more issues of a periodical, one or more volumes (or the whole set) of an encyclopedia, etc.
Tankōbon do not include bunkobon (typically used for novels), shinsho (新書, typically used for non-fiction), or rather larger-format mook (ムック, mukku, a blend of "magazine" and "book"), as each is within a series.
Tankōbon may be of any dimensions, from a miniature-sized novelty book (i.e. mamehon, 豆本) to a sumptuous folio-sized one. Nonetheless, oddly-sized tankōbon tend to be given a taxonomical name.