In Linz I have heard the word präpotent for describing another person. I enjoyed this - for me - new word. Is it specific to Austrian German?
Präpotent is interesting in that its meaning depends on the register it's being used in - its original meaning is used in high register speech as "overwhelmingly powerful", the more colloquial register is "pretends to be" the above (i.e. being arrogant, pretentious).
I have indeed the feeling (no proof) that the more derogative use is predominantly actually originating from Austria, as I've only ever heard it in that usage in the south (Austria, Bavaria). Online Duden seems to confirm the Austrian origin of that usage, but I've seen it used in Swiss and German newspapers in that meaning as well.
This is a very interesting question. I only can tell about how I perceived this word in the last 50 years where I lived, in the eastern parts of Austria.
I was born in Austria (in Graz) in 1965, and except for a few month in London in 2013 and short holidays that I spent mainly in Italy, I spent my whole live in Austria: 1965-1996: Styria1 (mainly in and near Graz, but also 3 years next to Leoben and Bruck/Mur), 1997-2015: Vienna2 (in the districts 20, 16, 10, 11 and then 16 again3), 2016 until now: Lower Austria4 (St. Pölten). (I have changed my residence 15 times in the last 40 years.)
My father (born near Feldbach in the south-east of Styria) used the word präpotent a lot when he talked about his bosses or local politicians and I also heard it quite often from other people in Graz in similar contexts. They all agreed on the meaning of this word: It is used as an adjective for people, with the intention of describing them as pretentious and arrogant. Only persons are präpotent; those who are präpotent are condescending, arrogant and presumptuous. I never have heard someone use this word in any other meaning. The meaning »overwhelmingly powerful« that was mentioned in another answer was completely unknown to me until I read this answer a few minutes ago.
When I left Graz, I lived for 3 years in a small village between Leoben and Bruck an der Mur, about 60 km north of Graz. I do not remember to have heard the word präpotent when I lived there, but maybe I just can't remember. The occasions when one might use this word are rare, and in these 3 years such occasions probably rarely occurred.
In January of 1997 I moved to Vienna (about 200 km north-northeast of Graz) where people use a language as colloquial speech, that is very different form the colloquial speech you can hear in Graz. It is not as different as dialects spoken in Germany differ from Austrian dialects, but Viennese colloquial speech is notably different for someone who is used to Styrian dialects and colloquial speech only.
I remember to heave heard the word präpotent in Vienna too, but with a significantly lower frequency than I remember it from Graz. It's hard to say if the reason is the different city or if it is just the time (before and after 1997).
Now (since 2016) I live in St. Pölten (70 km west of Vienna), and I do not remember to have heard this word at all here in the capital city of Lower Austria. And again, I don't know if the reason is the region or the time. I still visit Vienna quite often (about 80 times a year), and I also can't remember to have heard the word präpotent there in the last 6 years, so I guess the word has just become less frequent in Austria in the last decades.
I am sorry, I do not have any knowledge about the usage of this word in other regions. When I lived in Graz, I believed that every German native speaker uses this word with the same meaning and frequency as we did in Graz. But since I moved to other places, not really far away from where I've been born, it seems to me, as if this word is a term typical for Graz and the regions next to it.
1, 2, 4Austria (note, that there is no L in Austria, so, it's not Australia!) is a federal nation like USA, Mexico, Germany, India and many other countries. It consists of 9 states. Styria (Steiermark) (don't forget the T in Styria!), Vienna (Wien) and Lower Austria (Niederösterreich) are three of them, they are all located in the populous eastern region of Austria. (In the western part, the Alps take up a lot of space.) Austria has 9 million residents, 4,9 million people live in the three named states (1,9 million in Vienna)
3Vienna is divided in 23 districts. Viennese people usually refer to them by their numbers. The districts have well-known names too, and these names are also used sometimes, but instead of »Ich wohne in Favoriten.« people prefer »Ich wohne im zehnten Bezirk.« And because it's clear that they mean »Bezirk« they usually omit this word. So the most frequent version is: »Ich wohne im Zehnten.« The names of the districts mentioned above are: 20 = Brigittenau; 16 = Ottakring; 10 = Favoriten; 11 = Simmering.