Other Words for Grievous
Grievous as a Verb has these synonyms:
egregious, awful, flagrant, terrible, outrageous, heinous, dreadful, atrocious, monstrous, appalling, shocking, deplorable, calamitous, lamentable, intolerable, shameful, unbearable
Example: Missing that catch was a grievous error.
Example: The church buildings suffered grievous damage from the storm. He was charged with causing grievous bodily harm.