rectification

from The Century Dictionary.

• noun In its specific use in relation to the increase of strength of alcoholic liquors by distillation, rectification signifies repeated fractional evaporation of the mixed liquid, dephlegmation repeated fractional condensation of the mixed vapor. Both words are simultaneously applied in the improved forms of still.
• noun In astral., the ascertainment of the true time of birth by comparison of the directions deduced from the estimated time with the dates of events in the native's life.
• noun The act or operation of rectifying.
• noun The process of refining a substance by repeated or fractional distillation: it is in this way freed from other substances which are either more or less volatile than itself, or from non-volatile matters: as, tho rectification of spirits. The concentration of sulphuric acid in platinum or glass vessels is sometimes (improperly) called rectification.
• noun In geometry, the determination of a straight line whose length is equal to a given portion of a curve; the finding a formula for the length of the arc of a given curve.

from the GNU version of the Collaborative International Dictionary of English.

• noun The act or operation of rectifying
• noun (Geom.) The determination of a straight line whose length is equal a portion of a curve.
• noun (Astron.) its adjustment preparatory to the solution of a proposed problem.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun The action or process of rectifying.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun the conversion of alternating current to direct current
• noun the act of offering an improvement to replace a mistake; setting right
• noun (chemistry) the process of refinement or purification of a substance by distillation
• noun determination of the length of a curve; finding a straight line equal in length to a given curve