(simile, informal) Extremely dark; pitch-black.

Junco hyemalis, a passerine bird in the passerine family Passerellidae.

(of a potential romantic partner) Mysterious and physically appealing.

(politics) An informal group of commentators who oppose what they regard as the dominance of identity politics, political correctness, and cancel culture in higher education and the news media within Western countries.

plural of crater of eternal darkness

(space science) A crater or other depression, on a solid, non-luminous celestial body, the interior of which contains one or more points which lie in perpetual shadow due to a combination of high latitude and being on a celestial body with low axial tilt.

plural of dark crimson underwing

Catocala sponsa, a species of underwing moth.

(information technology) The lack of historical information in the digital age as a direct result of outdated file formats, software, or hardware that becomes corrupt, scarce, or inaccessible as technologies evolve and data decays.

(astronomy, physics) dark matter comprising elementary particles whose composition is as yet unknown, but is presumed to be unlike normal protons, neutrons and electrons etc.