The Latin adverb sic (/sɪk/; thus, so, and in this manner) inserted after a quotation indicates that the quoted matter has been transcribed or translated as found in the source text, including erroneous, archaic, or unusual spelling, punctuation, and grammar.
The typical editorial usage of Sic is to inform the reader that any errors in a quotation did not arise from editorial errors in the transcription, but are intentionally reproduced as they appear in the source text being quoted; thus, sic is placed inside brackets to indicate it is not part of the quotation.
Sic can also be used derisively to direct the reader's attention to the writer's spelling mistakes and erroneous logic, or to show disapproval of the content or form of the material.
[2] The immoderate use of sic has created some controversy, leading some editors, including bibliographical scholar Simon Nowell-Smith and literary critic Leon Edel, to speak out against it.
[9] The bracketed form [sic] is most often inserted into quoted or reprinted material to indicate meticulous accuracy in reproducing the preceding text, despite appearances to the reader of an incorrect or unusual orthography (spelling, punctuation, grammar, syntax, fact, logic, etc.).
[2][10] Several usage guides recommend that a bracketed sic be used primarily as an aid to the reader, not as an indicator of disagreement with the source.