This is the 2953rd most frequent Polish word.
niższych
"Niższych" means "lower" or "of lower" in English, used in the comparative or descriptive sense.
In this sentence, 'niższych' is an adjective in its genitive plural form, used to describe 'ceny', indicating a comparative quality of being lower.
Ceny produktów w sklepach stają się coraz niższych.
The prices of products in stores are becoming lower.
Here, 'niższych' is an adjective in its genitive plural form, modifying 'klas', and it marks a hierarchy or ordinal characteristic.
Studenci z niższych klas mogą uczestniczyć w programie doświadczalnym.
Students from lower grades can participate in the experimental program.
In this usage, 'niższych' functions as an adjective in its genitive plural form, referring to 'strukturach organizacyjnych', specifying a location condition in hierarchy.