atrum

atrum is a Latin form of ater, meaning “black, dark; gloomy, deadly”. It is the genitive plural neuter adjective or genitive plural masculine adjective or accusative singular masculine adjective or nominative singular neuter adjective.

Found 29 times in the Latin texts on Socratos.

Where it is used

Vergil, Aeneid 1.165: desuper horrentique atrum nemus imminet umbra.

All forms of ater (declension table)

Source: Socratos (socratos.org), a free reader for Ancient Greek and Latin. Grammar from the Perseus Treebank and Morpheus; dictionary entries from Lewis & Short, A Latin Dictionary (Perseus Digital Library, CC BY-SA). Counts are from the texts on Socratos.