red-lettered
/ˈrɛdˌlɛtəd/adjective
Characterized or indicated by red letters; written in red; marked out for particular attention with, or as with, red letters; memorable, significant, noteworthy.
- In earlier use, with reference to the use of red letters to indicate a saint's day or feast on an ecclesiastical calendar..
Origin
Mid 17th century; earliest use found in Mercurius Politicus. From red letter + -ed.