1. the quality or state of being impossible to understand or interpret; mysterious or enigmatic nature

Examples

• The inscrutableness of her expression made it difficult to know what she was thinking.
• The ancient text's inscrutableness has puzzled scholars for centuries.
• He spoke with such inscrutableness that no one could determine his true intentions.
• The inscrutableness of quantum mechanics challenges even experienced physicists.
• Her face maintained an air of inscrutableness throughout the entire interview.
• The inscrutableness of the painting's meaning has sparked countless interpretations.