This is the 11201st most frequent Russian word.
грузовых
"Грузовых" means "cargo" or "freight" (adjective).
The word 'грузовых' is used here as an adjective modifying 'машин', meaning 'cargo trucks' or 'trucks for carrying loads'.
На складе стояло много грузовых машин.
There were many cargo trucks parked in the warehouse.
In this sentence, 'грузовых' describes 'перевозок', referring to transportation specifically for goods and cargo.
Развитие грузовых перевозок имеет большое значение для экономики.
The development of cargo transportation is very important for the economy.
Here, 'грузовых' qualifies 'доставок', emphasizing deliveries of goods or freight.