locking plate

noun Horology.
  1. a narrow wheel geared to a striking train or other mechanism and having a notched rim engaging with another mechanism permitting it to rotate through a specific arc.

Origin of locking plate

First recorded in 1875–80
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for locking plate

Historical Examples of locking plate