How do you pronounce circa in Latin?

It’s simply that in classical Latin, ‘c’s were always pronounced hard, as in ‘k’. Hence the pronunciation ‘kirka’.

What does circa mean?

: at approximately, in approximately, or of approximately —used especially with dates born circa 1600.

What is a correct pronunciation?

Pronunciation is the way in which a word or a language is spoken. This may refer to generally agreed-upon sequences of sounds used in speaking a given word or language in a specific dialect (“correct pronunciation“) or simply the way a particular individual speaks a word or language.