(in color printing) the plate providing the greatest definition of detail, usually the black plate, on which the other plates are registered.
What Does 🔑 Key Emoji Mean?Not to be confused with the old key emoji ... the key emoji depicts a single key, and it's presented in varying shades of brass and silver on various platforms.
Origin of key plate
First recorded in 1905–10
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for key plate
By giving the key a quarter-turn the slit in the key-plate compresses the springs, and they are then withdrawn from the lock.On the Development and Distribution of Primitive Locks and Keys|Augustus Pitt-Rivers
This done, we next take the frame and remove the key-plate from it.