IPA: /kəˈlæmɪtəsli/
KK: /kəˈlæmɪtəsli/
In a way that causes great damage or distress.
The storm calamitously affected the entire region, leaving many without homes.
Calamitously → It is formed from "calamity" (from Latin *calamitas*, meaning disaster or misfortune) and the suffix "-ously" (meaning in a manner characterized by). The word "calamitously" means in a manner that is disastrous or characterized by misfortune.
Think of 'calamity' as a disaster and remember that 'calamitously' describes something done in a disastrous way.