The black oxide of manganese, MnO₂.

A coarse, sponge-like form of elemental palladium that offers a large surface area for hydrogen adsorption and can be used as a catalyst for hydrogenation reactions.

Having a black eye. / Having the iris of a black color. / as a part of a phrase

(phytopathology) A disease of wheat, in which a black, moist substance is deposited in the fissures of the grain.

malignant anthrax with engorgement of a shoulder or quarter, etc., as of an ox

Any of several plant diseases causing the formation of dark cankers. / The larva of the turnip sawfly (Athalia rosae), an agricultural pest having the appearance of a black caterpillar.

plural of black raspberry

(simile) Very black (especially of a mood, a frown, etc.).

Fraxinus nigra, a species of ash tree native to much of eastern Canada and the northeastern United States. / Acer negundo, a North American maple. / Eucalyptus sieberi, an Australian tree.

(usually considered derogatory) The Superior General of the Society of Jesus.