Black Letter

Part of speech: noun (n.)

The old English or Gothic letter, in which the Early English manuscripts were written, and the first English books were printed. It was conspicuous for its blackness. See Type.

Part of speech: adjective (a.)

1. Written or printed in black letter; as, a black-letter manuscript or book.

2. Given to the study of books in black letter; that is, of old books; out of date. Kemble, a black-letter man! J. Boaden.

3. Of or pertaining to the days in the calendar not marked with red letters as saints' days. Hence: Unlucky; inauspicious.