Not sure whether the Norwegian equivalent of "ab-" and "aus-" is both "av-", I don't speak Norwegian.

Also: The etymology section on that dictionary entry is spanning all three meanings, which I find somewhat doubtful. Like, yes, the "animal training" meaning certainly relates to German "abrichten", but the other two might've developed a life of their own in Norwegian.

Is there maybe a second meaning of
"avrette"?

Hmm. But what bothers me is that Norwegian have two words that are similar, but not very similar. One of them (henrette) means execute. The other (avrette) means either execute or level. Although the former is an older meaning I guess.

And here I am, trying to figure out why we have two words for "execute". And the dictionaries "blame" both words on German. Which seems to be wrong. And I am further from an answer...

But thanks for answering!

I suspect what's going on here, especially with the example of "afrette en synder", is that it's a somewhat archaic specialized form of "richten" ("to judge").

The prefix "ab-" (probably somewhat equivalent to English "off-") can imply some finality, closure, an ending. I could see how convicting ("richten") someone to be punished by death could've been called "abrichten" at some point, but no German would use it like that today, or even understand it.

First: abrichten does not mean execute.

Second: in German there are incredibly many words. Compared to Norwegian I think there are often much more nuanced words for the "same" thing, that can be either used interchangeably or differenciate much better than in Norwegian. So having two different words in German for sth that only has one word in Norwegian is quite common, I believe.

Hmm...

Abrichten is used for a wood shaping technology and the engine used for it. Sorry, the artikle is missing in bokmål.
https://en.wikipedia.org/wiki/Jointer

Both "henrette" and "avrette" means execute in Norwegian, although "avrette" more commonly is used to "level (a floor).

And this dictionary claims "avrette" comes from the German "abrichten":
https://naob.no/ordbok/avrette

The only meaning of "abrichten" I'm familiar with is "to train an animal" (with a subtext of "to have it perform serious tasks").