Sic

The Latin adverb sic ("thus"; "just as"; in full: sic erat scriptum, "thus was it written") inserted after a quoted word or passage, indicates that the quoted matter has been transcribed exactly as found in the source text, complete with any erroneous or archaic spelling, surprising assertion, faulty reasoning, or other matter that might otherwise be taken as an error of transcription.

The usual usage is to inform the reader that any errors or apparent errors in quoted material do not arise from errors in the course of the transcription, but are intentionally reproduced, exactly as they appear in the source text. It is generally placed inside brackets to indicate that it is not part of the quoted matter.

Sic may also be used derisively, to call attention to the original writer's spelling mistakes or erroneous logic.

Though occasionally misidentified as an abbreviated word, sic is a Latin adverb used in English as an adverb, and, derivatively, as a noun and a verb.

The adverb sic, meaning "intentionally so written", first appeared in English circa 1856. It is derived from the Latin adverb sīc, which means "so, thus, in this manner".

According to the Oxford English Dictionary, the verbal form of sic, meaning "to mark with a sic", emerged in 1889, E. Belfort Bax's work in The Ethics of Socialism being an early example.

On occasion, sic has been misidentified as an acronym (and therefore sometimes misspelled with periods): "s.i.c." is said to stand for "spelled in context", "said in copy", "spelling is correct", "spelled incorrectly", and other such folk etymology phrases. These are all incorrect and are simply backronyms from sic.

Use of sic greatly increased in the mid-twentieth century. For example, in United States state-court opinions before 1944, sic appeared 1,239 times in the Westlaw database; in those from 1945 to 1990, it appeared 69,168 times. The "benighted use" as a form of ridicule, deserved or otherwise, has been cited as a major factor in this increase.

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