@DreamsDragon is right. Another translation might be “official use”. When you look at the example sentences you can get a better feeling what it means (good thing there are 3 sentences now for lower levels).
今、公用でパリにきています。
I’m coming to Paris now on official business.
これは公用のアカウントです。
This is an official account.
おれたちがぬすむのは公用のかねだ。
We’re gonna steal government money.
i’ve got a similarly clunky one. i imagine that the national one is better than the local one; therefore they do all the 察ing, while the metros just sit idly by and watch 観. so far i haven’t failed to keep them straight.
AND YET. i STILL, JUST failed to burn it.
not because i answered national, no. i typed “metropolitan police agency”.
if i wasn’t a stubborn holdout on not using the ignore script that’d have been an instant override.
Edit: I have no idea why I replied to your post in particular.
I used to have a full cheatsheet for this but the takeaway rule of thumb I ended up with was this:
For intransitive I just remember the phrase ‘waru.’ If a word ends with waru it’s 99/100 times gonna be intransitive. You can also take the first consonant off. So waru → aru. If it ends with an aru it’s the same.
For transitive remember ‘yasu.’ Same concept, if it ends with ‘yasu’ you can bet it’ll be a transitive verb. You can take off the first consonant and get ‘asu.’ Transitive. You can go a step further and take off a second character here. ‘su.’ It’s transitive.
In short:
Always intransitive: ~waru ~_aru
Always transitive: ~yasu, ~_asu, ~__su.
I’m looking at the chart here right now. Another take away:
If a verb has an ‘s’ around the ending, it’ll probably be a transitive verb. ~yasu, ~asu, ~osu, ~seru are all transitive.
Reading the example sentences would have saved you here…
Generally, if you have a transitive and intransitive version, and one ends in る and one doesn’t, the る verb is the intransitive one.
There are some other rules in the link posted earlier in the thread, and some exceptions as well, but it’s a good starting place that will get you through a lot of WK’s vocab. (Though look out for the せる mutation listed above.)
For me? I still regularly get mixed up on the nuances between all the 願-ending nouns. Still have several floating around on WK.
Is there a badge for ‘confusion’?
Sweet baby Jesus, those two give me a headache almost every time! lmao 
It doesn’t help that they are both KaK~
If the readings were totally different then it would be a lot easier.
Like 訪れる 訪ねる or something.
おとずれる たずねる
I used to get 欠かす wrong a lot; now I use the alternative meaning “to fail to attend” to remember it like this:
“If you miss the meeting, someone will sue (す) you”
What exactly is stupid? That 欠かす has that meaning?
欠席 is the formal (noun) term for absence if this enforces that anymore.
It’s more of a rage thing, but yeh every time it throws me off since it seems like it should be something else.
My way of dealing with these @#$%ers was to just cheat. Screw it, if I ever need to tell the difference between them, I’ll learn it at the time.
支度 meaning makes no sense to me, and the exceptional reading doesn’t help.
Same. I always write ‘longstanding’ for that one.
The first stage of PREPARATION is to cut the SHIITAKE mushrooms.
Although they are spelled differently したく / しいたけ, when I say it in my head it works for me.
You may also be interested in learning the difference between a few other words that have the same or similar meaning.
There are definitely some words I have problems with, especially words that I learned one meaning first which wasn’t the “main” meaning.
But I have bigger problems such as properly using things like なんか and なんて, なんだと etc etc because they’re never really taught very well. And then as well some concepts like ほど
I have many, but I can’t remember them, hence part of the problem. But I just ran into this during reviews:
結局
How and why does that mean ‘after all’?
It comes from shogi.
局 is used to refer to the board in shogi, or, more abstractly, the situation of the game, the positions of the pieces. You should see “board” as a meaning if you look up English meanings, and it’s this meaning, not a general “board” like for building a house or something.
結局 would be the final position of the game, the end result.
It moved into regular language usage, similar to how “checkmate” did in English, though they’re not one-to-one equivalents obviously.
Other shogi terms that use 局 include
一局 - one game of shogi
対局 - playing shogi
局面 - the state of the board at any point in time during the game
Thank you. Now I will probably remember it forever!