Explaining the relationship between “short”, “kurz” and “curzu”

Question

I've recently noticed something that I can't explain, a link between German and Sardinian. Two languages that, at least apparently for me, are not supposed to be that linked. Also English is included in this, which is more related to German than it is to Sardinian. Yet there's something I cannot understand.

Let's take the word "short". In German it's kurz. I might be way off, but it seems that they do have some connection, k- with sh-, -o- with -u- and -rt with -rz, although my knowledge is not that deep so, like I said, I might be wrong on it.

But the relation seems much closer between German-Sardinian than German-English. In Sardinian, note that I'm speaking about the variant present in the middle of the island which is included in the macro-variant Logudorese¹, the word for "short" is "curzu" or "curza" according to the genre of the noun it refers to (e.g. un'istrada curza = a short street).

So, how could it be explained that we have "short/kurz" and "kurz/curzu"? Is there something I'm missing?

For what it's worth, in Italian we do have "corto", but I'm not sure what role it might have in this.

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^{1: Although my dialect is included in it, they are slightly different. For the purpose of the question I think we can ignore this difference, unless the answerers have reasons to think differently in order to answer the question.}

Answer 1

I suppose the short answer is that both German and Sardinian are Indo-European languages, so it's to be expected that they'll have some common word-forms. German is classed as Germanic and Sardinian is classed as a Romance language, but that doesn't mean that their development is completely separate: they shared a common ancestor. You can see the same if you compare French and German, for example. Words like "window" (fenêtre / Fenster) are obviously from the same root in French and German (i.e. Latin fenestra). Welsh has the same root for its word, ffenestr, although Welsh is categorised as a Celtic language. The English word is unusual here, as English didn't take window from Latin, but rather uses a native Germanic-derived form, from the words for wind and eye. (Although note that the word fenester was also in use in English until the 1500s).

The question of the relationship between German, Sardinian, and English falls into the trap of looking at the wrong data, I'm afraid. The English word that's comparable here is curt, not short. German kurz, Sardinian curzu/a and English curt all come from Latin curtus, as Alex B. pointed out in the comments. (The etymology of short is disputed, though it may also ultimately derive from curtus.) French court, Italian corto, Dutch kort, also all derive from the same root.

In summary, the fact that any two Indo-European languages have vocabulary in common should not come as a surprise. Much of this vocabulary comes, directly or indirectly, from Latin, and is not usually a sign of particular relatedness between the two languages unless it can be proven that Language A took a lot of its word forms from Language B as an intermediary, and not directly from Latin (or indeed from Language C, or Language D, etc.)