Complication (noun)

1. A problem or difficulty that arises in a situation.
2. A secondary or accompanying condition or circumstance.
3. A complex or involved situation or arrangement of events or circumstances.

Origin:

Late middle english: from latin complicatio(n-), from complicare "to fold together", from com- "together" + plicare "to fold".

Examples:

1. The complication of his injury resulted in a longer recovery time.
2. A major complication of diabetes is an increased risk of heart disease.
3. The deal was already complicated enough without these new complications.
4. The complication of the legal system made it difficult for the average person to understand.
5. The complications of modern life seemed to be increasing every day.