means A motor vehicle built to carry cargo or heavy loads, ranging from a small pickup to a hulking tractor-trailer.

from The modern "big vehicle" sense is American, but the word is older and humbler: "truck" first named a small wheel or roller — the kind under a cannon carriage or a cart. It likely traces back to Latin "trochus," an iron hoop, from Greek "trokhos," a wheel (from "trekhein," to run). So the truck was once just the wheels; the metal beast that rolls on them inherited the name.