My days of decent knowledge of Latin are a little in the past since I passed my Latinum, and I am trying to get a good translation for what modern US courst call "vexatious litigant" into Latin for a little joke to a lawyer friend of mine - because illnesses have often latin names and there's a lot of law-latin around. I was planning to use it this construction in combination with the imperative abstine for "keep away the vexatious litigant".
The best translation for the word vexatious I could find is the root of it: vexatio, vexationis in it's 4th meaning of "trouble, vexation".
Now Litigant also has a fitting latin stem in litigere, litigo, in its 2nd meaning "to litigate/sue".
But here I get to the end of my latin: How to properly combine the two to get the vexatious litigant?