This is the 6385th most frequent Russian word.
центральных
The Russian word "центральных" means "central" (genitive or plural form).
Here, the word 'центральных' is an adjective in the genitive plural form, modifying 'улиц' (streets), denoting their characteristic of being central.
Я люблю прогулки около центральных улиц города.
I love walks near the central streets of the city.
In this sentence, 'центральных' modifies 'районах' (districts) and describes their location or prominence as central areas.
В центральных районах всегда много людей.
In the central districts, there are always many people.
The word 'центральных' describes 'систем' (systems) as being 'central', frequently found in multi-residential buildings or main facilities.