opacous

== English == === Etymology === From Latin opacus (“shaded, shady, dark”) +‎ -ous. === Adjective === opacous (not comparable) (obsolete, chiefly poetic) Not shining or illuminated; dark. [17th–20th c.] (obsolete) Not allowing the passage of light; opaque. [17th–19th c.] ==== Derived terms ====