TENEBROUS Meaning of TENEBROUS in English [ten.e.brous] adj [ME, fr. MF tenebreus, fr. L tenebrosus, fr. tenebrae] (15c) 1: shut off from the light: dark, murky 2: hard to understand: obscure 3: causing gloom Merriam-Webster English vocab. Английский словарь Merriam Webster. 2012