prep. 25B6; preposition APPROXIMATELY, (round) about, around, in the region of, roughly, something like, of the order of, or so, or thereabouts, more or less; informal as near as dammit; N. Amer. informal in the ballpark of.
exactly.
CIRCA
Meaning of CIRCA in English
Concise Oxford thesaurus English vocabulary. Краткий оксфордский словарь английского языка тезаурус. 2012