complication (n.)
early 15c., from Middle French complication, from Latin complicationem (nominative complicatio), noun of action from past participle stem of complicare "to fold together, fold up, roll up," from com- "together" (see com-) + plicare "to fold, weave" (see ply (v.1)). Meaning "something that complicates" first recorded 1903.