nigrous

From Latin nigrum, +‎ -ous.

nigrous (not comparable)

1. Black.
   • 1816, George Thomas, Freedom; with other poems:

     Of pillared mists, in nigrous smoking gloom, […]

   • 1940, Stanford University, Natural History Museum, Microentomology: Contributions to Entomology from the Natural History Museum of Stanford University, Volumes 5-8:

     Sternum: nigrous, clad less densely with longer, usually fusiform, similarly colored squamae; […]

   • 2008, Glen Craney, The Fire and the Light: A Novel of the Cathars and the Lost Teachings of Christ:

     At this hour, just before dawn, another nigrous presence came hovering over him to darken his face.

• rousing, rugosin, souring