This is the 10070th most frequent Russian word.
аэропортов
"Airports" (genitive plural form of аэропорт).
Here the word 'аэропортов' is in the genitive plural form, indicating ownership or relation when counting non-specific instances of 'аэропорт' (airport).
В этом регионе находятся четыре крупных аэропортов.
In this region, there are four major airports.
The word 'аэропортов' is in the genitive case to show possession or association ('schedules of airports').
Я наблюдал за расписанием вылетов нескольких аэропортов.
I observed the flight schedules of several airports.
Similarly, 'аэропортов' here indicates a plural genitive for showing relation ('service of airports').