noun. A tool having a thin triangular head, used to crease leather.

noun. A tool for creasing or crimping cartridge-cases.

noun. In bookbinding, a tool which creases and sharply defines the width of the bands of books, and fixes the position of lines on the backs and sides, the lines being afterward covered by a blind roll or blind stamp.

noun. An attachment to a sewing-machine for making a crease to serve as a guide for the next row of stitching.

noun. A tool, or a sewing-machine attachment, for making lines or creases on leather or cloth, as guides to sew by.

noun. A tool for making creases or beads, as in sheet iron, or for rounding small tubes.

noun. A tool for making the band impression distinct on the back.

noun. A tool or attachment for making creases or guidelines.

"With the right side down, fold all the flaps in towards the middle, and crease using your popsicle stick or paper creaser(sometimes these are called “bone folders” though they are generally made from plastic nowadays). glue the large side flap over the top of the folded in bottom (the tapered end is the top) and opposite side flap."