This is the 8301st most frequent Russian word.
мерефе
It appears "мерефе" does not correspond to a standard Russian word. It may be a proper noun, regional term, or misspelling.
Here, 'мерефе' refers to a proper noun, specifically a city name, and is used as a subject in the sentence.
Я слышал, что мерефе — это город недалеко от Днепра.
I heard that Merefe is a city near Dnipro.
In this context, 'мерефе' continues to denote the city but functions as the object 'through Merefe,' indicating a location visited or passed.
Когда я путешествовал по Украине, я проезжал через мерефе.
When traveling through Ukraine, I passed through Merefe.
Here, 'мерефе' remains a place name but is used in the prepositional context 'in Merefe,' explaining where the action took place.