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Circa (from Latin , meaning 'around, about') – frequently abbreviated c., ca. or ca and less frequently circ. or cca. – signifies "approximately" in several European languages and as a loanword in English, usually in reference to a date. [1] Circa is widely used in historical writing when the dates of events are not accurately known.

A loanword is a word adopted from one language and incorporated into another language without translation. This is in contrast to cognates, which are words in two or more languages that are similar because they share an etymological origin, and calques, which involve translation.


When used in date ranges, circa is applied before each approximate date, while dates without circa immediately preceding them are generally assumed to be known with certainty.


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  1. "circa". . Retrieved 16 July 2010.