A Rectification

1. The action or process of rectifying.
2. (geometry) The determination of a straight line whose length is equal to a portion of a curve.
3. (geometry) The truncation of a polyhedron by replacing each vertex with a face that passes though the midpoint of each edge connected to the vertex; an analogous procedure on a polytope of dimension higher than 3.https://en.wikipedia.org/wiki/Rectification_(geometry)
4. (astronomy) The adjustment of a globe preparatory to the solution of a proposed problem.
5. (chemistry, chemical engineering) Purification of a substance through repeated or continuous distillation.
6. (politics, historical) Any of a number of Chinese and Filipino communist purges. See rectification movement.
7. (astrology) A procedure that attempts to determine a person's time of birth based on events in their life.