adjective Allowing little light to pass through, not translucent or transparent.
adjective Unclear, unintelligible, hard to get or explain the meaning of.
adjective Obtuse, stupid.
adjective Describes a data type for which higher-level callers have no knowledge of data values or their representations; all operations are carried out by the type's defined abstract operators.
noun An area of darkness; a place or region with no light.
noun Something which is opaque rather than translucent.