Collating mark: A distinctive rectangular mark, or short thick rule printed at successively lower positions on the spine of adjacent sections of a book, forming a stepped pattern, to denote correct gathering sequence.

• 帖标:印在帖脊上的显著黑色方块或粗黑线条；它们顺着帖次向下移动，组成梯级图案，表示各帖的次序正确。