Definify.com
Webster 1913 Edition
Black-letter
Black′-letˊter
,Adj.
1.
Written or printed in black letter;
as, a
. black-letter
manuscript or book2.
Given to the study of books in black letter; that is, of old books; out of date.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; – compare
red-letter
. Hence:
Unlucky; inauspicious.