1. the quality or state of being complex; having many interconnected parts or aspects that are difficult to understand or deal with
Usage: plural of complexity
2. complicated or intricate details, features, or elements of something
Usage: plural of complexity

Examples

• The complexities of the tax code make it difficult for ordinary citizens to understand.
• She studied the complexities of human behavior in her psychology course.
• The project failed because we underestimated the complexities involved.
• Modern technology has added new complexities to our daily lives.
• The legal complexities of the case required expert consultation.
• Scientists are still unraveling the complexities of the human brain.
• The complexities of international trade agreements affect global economics.