This is the 8916th most frequent Russian word.
псковская
"Pskovskaya" refers to something related to Pskov, a city or region in Russia.
The word 'Псковская' here functions as an adjective derived from the geographical name 'Псков' and describes the fortress, indicating its relation to the city of Pskov.
Псковская крепость была построена в XIII веке.
The Pskov fortress was built in the 13th century.
The word 'Псковской' in this sentence modifies the noun 'улице' (street), with its form indicating agreement in case, number, and gender.
Мы направляемся по Псковской улице к рынку.
We are heading along Pskovskaya Street to the market.
Here 'Псковская' describes the painting, implying that it originates from the region of Pskov, serving as an attributive adjective.