Sic comes from Latin and means so, thus, in this manner.

Sic erat scriptum means so written, thus it had been written.

When quoting something, writers may use sic to indicate that a word or phrase that looks wrong is indeed an exact reproduction of the original—the mistake appears in the source. Quotations should always be in their original form.

Sic is usually written in square brackets: [sic]. The word sic is often seen as a loanword that does not require italics, but in the United States, sic is usually italicized.

Sic can be used to mark an actual error or misprint or a conspicuous detail in the text, a word that seems odd or erroneous.

Since sic is used to draw the reader’s attention to a mistake by the writer, it often indicates disapproval and may signal superciliousness or be condescending. You should use caution when writing [sic] in order not to sound haughty or malicious.

There [sic] son had graduated from Cambridge.
The correct spelling is, of course, their.

She carries out research at the John [sic] Hopkins University.
This is a common error. The correct name is Johns Hopkins University, named after the entrepreneur and benefactor Johns Hopkins. His great-grandmother’s name was Margaret Johns; she married Gerard Hopkins and they named their son, the benefactor’s grandfather, Johns Hopkins. His grandson had the same name.

You can find a number of Latin abbreviations used in English here.