the act of complicating.

a complicated or involved state or condition.

a complex combination of elements or things.

something that introduces, usually unexpectedly, some difficulty, problem, change, etc.

Because of the complications involved in traveling during the strike, we decided to postpone our trip.

Pathology . a concurrent disease, accident, or adverse reaction that aggravates the original disease.

the act of forming a unified idea or impression from a number of sense data, memories, etc.

noun

ease , peace , simplicity , disentanglement

noun

aggravation , complexity , confusion , development , difficulty , dilemma , drawback , embarrassment , entanglement , factor , intricacy , obstacle , problem , snag , web , catch , convolution , fly in the ointment , hitch , illness , imbroglio , involution , ramification , snarl , tangle