German technical texts tend to be liberally littered with the abbreviation “ca.” to indicate that what follows should be read as an approximation. Usually our preference has been to render this Latin term for “about” or “around” as “approx.” when translating into English. This can, however, be awkward, as that may appear too long in tables and other contexts. Is there an alternative? If we seek an expert opinion, The New Oxford Style Manual has this to say on the matter:
“The Latin circa, meaning ‘about’, is used in English mainly with dates and quantities. Set the italicized abbreviation c. close up to any figures following (c.1020, c.£10,400), but spaced from words and letters (c. AD 44). In discursive prose it is usually preferable to use about or some when describing quantities”.
Further discussions with other linguists led to the conclusion that circa / c. is indeed mostly seen in relation to dates in English texts, as also reported at Wikipedia, whereas the German ca. can precede both figures that are dates and figures that are quantities. More generally, it seems that the New Oxford Style Manual tends to be geared towards non-technical texts. CA also already serves as an abbreviation for California, and for the Catalan language, and .ca is the domain ending for the entire country of Canada, and so that takes us roughly back to “approx.” when dealing with numbers. Or should we introduce the tilde symbol so often used in scientific and technical contexts: “~”?
The tilde symbol precedes an approximate value and appears on the standard keyboard and provides a standard notation in an efficient single character. The internet and emoji age, and text messaging, have in fact brought new pressures for abbreviation and compactness in language, and new uses of old symbols. In texting, instant messaging and internet speak “~” has two new, different and confusing usages: as a suffix to imply endearment, or alternatively to bracket a word to influence its meaning with a sarcastic or embarrassed undertone.
The tilde itself might be replaceable by an emoji moustache, but only one emoji 👨, the man emoji, has a moustache and currently only some of the time depending on who is delivering it and how many pixels they have shaved. Using that emoji in translations would be an approximate and unreliable solution until a formal moustache emoji is finally issued, so for the time being in technical texts in English we must come full circle back to “approx.”. More or less.