ˈtenəbrəs adjective
Etymology: Middle English, from Middle French tenebreus, from Latin tenebrosus, from tenebrae (plural) darkness + -osus -ous — more at temerity
1.
a. : shut off from the light : dark , murky
a tenebrous cave
a tenebrous forest
b. : tenebrist
2. : hard to understand : mysterious , obscure
a tenebrous affair
a tenebrous theory
3. : gloomy
moderates our tenebrous and fantastical imaginations — Rose Macaulay
• ten·e·brous·ness noun -es