noun
source book; reference book; source material
Refers to a book used as a source of information, ideas, or material for writing, research, or creative work. Often implies a primary or foundational text.
この小説の種本は、江戸時代の随筆だと言われている。
The source book for this novel is said to be an essay from the Edo period.
論文を書くために、何冊かの種本を集めた。
I gathered several reference books to write my thesis.
Compound of 種 (たね, 'seed; source; material') and 本 (ほん, 'book'). The combination literally means 'seed book', referring to a book that provides the seeds (material) for new work.