This is the 12737th most frequent Russian word.
красногорского
"Красногорского" means "of Krasnogorsk," referring to something or someone from Krasnogorsk, a city in Russia.
Here, 'красногорского' is used as a possessive adjective indicating the apple's origin.
Вкус красногорского яблока напомнил мне детство.
The taste of a Krasnogorsk apple reminded me of childhood.
In this sentence, 'красногорского' is an attributive adjective describing the region.
Я часто гулял по лесам красногорского района.
I often walked through the forests of the Krasnogorsk region.
Here, 'красногорского' serves as a descriptive adjective relating to the art's characteristic or origin.