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