Textual criticism: The scholarly discipline of establishing the text as near to the original as possible or probable (also known as lower criticism).

Since we no longer have any original manuscripts, or “autographs,” scholars must sort and evaluate the extant copies with their variant wordings.

...The textual critic not only sorts through manuscripts and fragments for copyist errors but also considers early translations (such as the Vulgate or Peshitta) and lectionaries for their witness to the text.

Patzia & Petrotta, Pocket Dictionary of Biblical Studies (2002), 114-115.