godan verb (-mu), intransitive verb
be folded under; be tucked inside
Describes something bending or being folded so that it goes under or inside something else, often used for pages, flaps, or edges.
本のページが折れ込んでいた。
The book's page was folded under.
布の端が内側に折れ込んでいる。
The edge of the cloth is folded inside.