A rare botanical or biological term describing something that is dark reddish-brown in color, combining atrocious/dark with a blue tone.
From Latin 'atrocis' (dark, fierce) + 'caerulea' (blue), a compound created in scientific nomenclature to describe specific color combinations observed in plants or minerals.
This is one of those wonderfully specific scientific words that vanished almost as soon as it was invented—it tried to describe a color you could capture in photography today in seconds, but in the 1700s describing plant colors required inventing hyphenated Latin monsters.
Complete word intelligence in one call. Free tier — 50 lookups/day.