I know what you're thinking out there, Brethren. A truck is a big vehicle with as many as eighteen wheels that barrels down the highway carrying goods who knows where but, at least in the States, probably to WalMart. What in heaven does that have to do with sailors? Or those lovely waves? Wait and see.
According to Websters the word truck, meaning the vehicle, comes from the Latin trochus meaning a hoop. In this sense a truck was originally a wheel and it grew from there. Masts often had trucks, either as caps at the head or as a block or disk made of wood with holes for rigging to pass through. Guns (meaning cannons) had trucks on which they rolled to accommodate their recoil. All of these then became our English word truck, the vehicle.
But maybe there's more to it. Another use of the word truck, though somewhat antiquated now, meant to barter or exchange. As the sailors word book puts it: ... as to truck fish for grog. Spoken like a seaman. Here Webster puts the origin of truck on the shoulders of the French troc; the verb troquer means to exchange. Truck could also mean wages, especially to a sailor. "Half-truck" meant a man was paid half his standard due on signing aboard and the rest on successful completion of the cruise. Truck was sometimes a word for garbage which may be the origin of "I will not truck with him", although most sources say that usage comes from the bartering meaning.
Finally, truck is a very old Cornish word for the trough between two waves. It was probably pronounced more like trock or troock than our modern truck and may have been the origin of the word trough itself.
Something to think about. Happy Saturday, Brethren. I'm off to truck with a mug of grog.