This is the 96th most frequent Russian word.
дома
"At home" or "houses" depending on context.
In this sentence, 'дома' is used as an adverb meaning 'at home'.
Я остался дома сегодня.
I stayed home today.
Here, 'дома' is the plural noun form of 'дом', meaning 'houses'.
Мои дома находятся на окраине города.
My houses are located on the outskirts of the city.
In this context, 'дома' is again an adverb, describing the state or location 'at home'.