fore edge (of a book)
Technical term in bookbinding and printing; refers to the front edge of a book opposite the spine.
製本の際、前小口をきれいに揃えることが大切です。
When binding a book, it is important to align the fore edge neatly.
Compound of 前 (front) and 小口 (edge, cut end), referring to the front edge of a book.