What is the protective plate on a door lock called?
Some doors have this plate that guards the latch mechanism.

You have one answer in that sentence,  Guard and latch, just reverse them to &quot;Latch Guard&quot;.
It is called many things,
A  &quot;latch shield&quot;
Or &quot;Door latch guard&quot;
Or &quot;Latch protector&quot;.
To name a few.