This is the 8368th most frequent Russian word.
мончегорска
"Мончегорска" is the genitive case form of "Мончегорск," referring to something "of Monchegorsk," a town in Russia.
The word 'Мончегорска' is used here in the genitive case to indicate origin from the city.
Я приехал из Мончегорска.
I arrived from Monchegorsk.
The form 'Мончегорске' is the prepositional case used to indicate being in, or related to, the city.
В Мончегорске прекрасная природа.
Monchegorsk has wonderful nature.
Here, 'Мончегорск' is in the nominative case as the object of visitation.