Definition of "black letter"

black letter

noun
countable and uncountable, plural black letters
1. (calligraphy) A highly calligraphic Western European script style used from approximately 1150.
2. (typography) A Northern European style of type, with contrasting thick-and-thin, angular strokes forming upright letterforms, and usually set with a dark typographic colour on the page.
  Quotations
  Also we discovered what is still more curious, an English version of the black-letter Latin.
  1886 October – 1887 January, H[enry] Rider Haggard, She: A History of Adventure, London: Longmans, Green, and Co., published 1887
  The original boldface printing types are the blackletters used by Gutenberg in the 1440s. For the next two centuries, blackletter fonts were widely used not only in Germany but in France, Spain, the Netherlands and Engand.
  2002, Robert Bringhurst, The Elements of Typographic Style (version 2.5), Vancouver: Hartley & Marks, page 103
3. Text set in black-letter type.
4. (law) The basic standard elements for a particular field of law, which are generally known and free from doubt or dispute.
  Quotations
  [The US Supreme Court] did not raise the fundamental normative question of the patent-ability of genes. Instead, it took a black letter approach to interpreting the Patent Act, which had first been enacted in 1790, and which in its current form states that “whoever invents or discovers any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof, may obtain a patent therefor, subject to the conditions and requirements of this title.”
  2020, Katharina Pistor, “5: Enclosing Nature's Code”, in The Code of Capital […] , Princeton University Press