If you're the sort to use fancy words, try Cleartext, a simple Mac text editor that won't let you.
It's the creation of Morten Just, who was inspired by Randall Munroe's Thing Explainer: "Use it to tell your family members why their computers act up, or tell people at work why they should pay you more."
Best of all, there's a Trump Mode, restricted to words used by Republican presidential candidate Donald Trump in his speeches.
Morten also collects responses from people angry at him because long words make you look smarter. I'm sure he's anaspeptic, frasmotic, even compunctuous to have caused them such pericombobulations.