[maaaaattttt]

I wish I could have sent this wikipedia entry to Mark Twain. It would have been a fine addition to his "museum". I'm sure he would have been thrilled to hear about it:

https://en.wikipedia.org/wiki/Rinderkennzeichnungs-_und_Rind...

[lqet]

The currently longest word in the Duden is Aufmerksamkeitsdefizit-Hyperaktivitätsstörung (ADHS, German for ADHD).