This is the 4063rd most frequent Russian word.
нарвской
The Russian word "нарвской" means "of or relating to Narva," a city in Estonia.
In this sentence, 'нарвской' acts as an adjective in the genitive case modifying the noun 'заставы' to describe the location related to 'Narva'.
Нарвской заставы покажите мне дорогу.
Show me the way to the Narva Gate.
Here, 'нарвской' is again an adjective describing 'улице', signifying the name of a specific street.
Он живёт на Нарвской улице.
He lives on Narva Street.
In this sentence, 'Нарвской' is an adjective modifying 'стороны', indicating the part of the town associated with 'Narva'.