emery board (plural emery boards)
an emery board
- An abrasive strip made by gluing grains of emery onto a rigid material, often used as a nail file.
2009, Chris Epting, The Early Polo Grounds, page 1948:He was known for throwing the “emery ball,” a baseball that had been scuffed with a piece of emery board hidden in the heel of his glove.
