emendation

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The act of emending.
• noun An alteration intended to improve.

from The Century Dictionary.

• noun The removal of errors; the correction of that which is erroneous or faulty; alteration for the better; correction.
• noun An alteration or correction, especially in a text: as, a new edition containing many emendations.
• noun Synonyms Amendment, rectification, reformation.

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

• noun The act of altering for the better, or correcting what is erroneous or faulty; correction; improvement.
• noun Alteration by editorial criticism, as of a text so as to give a better reading; removal of errors or corruptions from a document.

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

• noun The act of altering for the better, or correcting what is erroneous or faulty; correction; improvement.
• noun Alteration by editorial criticism, as of a text so as to give a better reading; removal of errors or corruptions from a document.

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

• noun a correction by emending; a correction resulting from critical editing