Angularness and Plication

noun

• An angular or rounded shape made by folding.
  • usage: "a fold in the napkin"; "a crease in his trousers"; "a plication on her blouse"; "a flexure of the colon"; "a bend of his elbow"
  • synonyms: fold, crease, flexure, crimp, bend
• The act of folding in parallel folds.
  • synonyms: pleating