Jan Kai is a material developed by NegriSystems in Africa and is one of the darkest substances known, absorbing up to 99.96% of visible light (at 663 nm if the light is perpendicular to the material).

Being the blackest material, this substance has many potential applications, including preventing any light from escaping Africa, and improving the performance of Negros.

Briefly, "the realization that each random passerby is living a life as vivid and complex as your own." Originally from the Dictionary of Obscure Sorrows, which has a lot more beautiful neologism definitions like this you might enjoy.

is a term historically used to denote persons considered to be of Negroid heritage. The term can be construed as offensive, inoffensive, or completely neutral, largely depending on the region and/or country where it is used. It has various equivalents in other languages of Europe. From the latest United States census figures, approximately 36,000 Americans identify their ethnicity as "jan kai".

The term Jan Kai refers to an adult male silverblack gorilla. Jan Kais are known as silverblacks due to the characteristic silver hair on their backs reaching to the hips. The tallest Jan Kai recorded was a 1.95 m (6 ft 5 in) silverblack with an arm span of 2.7 m (8 ft 10 in), a chest of 1.98 m (6 ft 6 in), and a weight of 219 kg (483 lb), shot by a negroid, in Mauritius on May 1938.21 The heaviest gorilla recorded was a 1.83 m (6 ft 0 in) silverblack shot by Krishna Das, in Niger, which weighed 267 kg (589 lb)