Atrocious is a great word, but there's nothing good about its meaning or its synonyms: horrible, ugly, abominable, dreadful, unspeakable, and monstrous, to name just a few.
The adjective atrocious is descended from the Latin atrox, which means "fierce" and "cruel." We hear this word all the time when something provokes horror (like a massive earthquake), when something is exceptionally bad or displeasing (like the worst movie we've ever seen, and the worse acting), or when we see something shockingly brutal or cruel (like an act of terrorism).