Ad acta.

I was reading a Russian post on Facebook when the Latin-alphabet phrase ad acta jumped out at me. Not being familiar with it, I looked for it in my fairly comprehensive Dictionary of Foreign Words and Phrases (hey, I’m a book guy, what can I say), but it wasn’t there, so I went to the internet like a good 21st-century denizen and found it in Wiktionary: ad acta German Alternative forms ● ad Acta Etymology Borrowed from Latin ad ācta. […] Adverb 1. (higher register) to the files etwas ad acta legen ― to be done with something (literally, “to file”) Usage notes In modern times this almost only occurs in the phrase “etwas ad acta legen”, which means to put something to the files or, figuratively, to close the matter on a topic. So it’s used primarily in German, which explains why it’s not in my English-language reference book… but it’s also used in Russian, doubtless due to the deep immersion in German culture it got before WWI. The Russian national corpus turns up two examples, both…