1964 Cent, Reverse "Ghost Bust"

Ghosting is one name for this but not the proper name.
I believe it's called indirect design transfer.
Unlike a clash where there is direct die to die contact it is a transfer of the image from one die to the other through the struck coins.
Every time a coin is struck a small amount of energy is transfered from the obverse die to the reverse die and vice versa.
After many strikes, with certain designs, and under certain conditions the accumulated transfered energy eventually deforms the opposite die.
Very common on silver dollars, often seen on other denominations.

I confirm DBM error description.

Progressive Indirect DesignTransfer.

Some additionnal information here:

https://www.error-ref.com/progressi...gn-transfer/