"Pollution" was used in English for the same purpose as the "poluce" you discovered in Czech:
https://en.wiktionary.org/wiki/pollution
"Recorded since the 1340s, as "discharge of semen other than during sex", later, "desecration, defilement" (1382), from Late Latin pollutio (“defilement”)"
Wow, I never thought to look up etymology of the word in English. Thanks!
Other half is Hungarian, she often uses "Not" in place of "No", "Did you make it to the school on time?" "Not".
Turns out that in Hungarian No/Not == Nem so when she translates it in her head she uses No/Not interchangeably and it's flip a coin on what comes out, I find it endearingly cute, "Did you remember the milk?" "Not!".
I still confuse her with "aye" as an affirmative yes (I'm from Yorkshire in England and we still use aye and to a lesser extent 'nay' as an emphatic no).
Every now and then I'll mess up when reading out loud a "c" ("ts" in Czech) if I'm not paying attention, or writing "ch" instead of "č" - but that's pretty rare.
It's not the letters that mess me up, but the "false friends" - words that look similar to some in English and that can be a pretty big deal. I'm gonna write something in weird pseudo-code, because I can't express it cleanly in English.
So if you learned both Czech/German as a second language you can have moments of "wait, wtf!?" here and there. Also: More? Why not: So a Czech person agreeing to go for a beer with you might say "no" meaning "yes". There's some other good ones in Czech actually - the word "poluce" looks like "pollution" but actually means "emission of semen in sleep".If it sounds like I'm complaining then I'm not - I love all this weirdness :)
* = actually reflection and cases make this more complicated still - could also be mého/mému/mém/mým/své/svého/svému/svém/svým depending on context