Truckle is recorded as a dialect name for a cheese from about the beginning of the nineteenth century, usually one that is cylindrical or barrel-shaped. Some of my dictionaries say it’s dialect still, but cheesemaker acquaintances tell me that today it’s a standard term in the industry for any barrel-shaped or cylindrical cheese that is taller than it is wide.
This sense of the word came to us from the Latin trochlea, “pulley wheel; sheaf”, related to the Greek trokhilia, “pulley”. Truckle came into the language some 600 years ago with that meaning, referring to a simple wooden wheel with a groove in it to guide the rope. Soon afterwards a type of furniture castor shaped like a slim disc was given the same name.
Perhaps its best-known use is in truckle bed, a low bed on small wheels that could be stored under the main bed in a room. This was used by personal servants who slept in the same room as their masters or mistresses; the truckle bed would be dragged out at night and stored away again in the morning. Someone who slept like this was said to truckle and the implication of being below someone of higher social status led about 1660 to the figurative sense of truckle under or truckle down — to take a subservient or an inferior position.
More recently we’ve re-borrowed the Latin original trochlea to describe features in humans and insects that look like pulley wheels.