Of a very dark blue. / Black with bluish highlights.

An American vulture species, Coragyps atratus, with black plumage. / A north African and Eurasian vulture species, Aegypius monachus.

(medicine) A chronic disease of the lungs caused by the long-term inhalation of coal dust.

(chemistry) A fine black powder of amorphous carbon manufactured by the incomplete combustion of natural gas or oil, and used as a pigment in the manufacture of ink and paint. Used as a filler in rubber like polymers and rubber. It helps the polymers resist deterioration by ultraviolet rays.

(medicine, historical) A pandemic outbreak of bubonic plague throughout Europe and most of Asia in the 14th century that killed nearly half the population of Europe and Asia.

Magic derived from evil forces, as distinct from good or benign forces; or magic performed with the intention of doing harm.

(countable) A light bulb that emits ultraviolet light, usually used to create the illusion that anything white is glowing. / (uncountable, slang) ultraviolet radiation/light

Tea leaves which have been "fermented" (actually, oxidized) before drying to enhance their flavour (cf. green tea). / (Britain) A cup of tea served without milk.

(idiomatic) Explicitly, in writing, clearly and without doubt or misunderstanding, without any grey areas. / (literally) Using shades of gray rather than color.

An omnivorous slug found in Europe and the Pacific Northwest, Arion ater, not always black, despite the name.