What does tonneau mean?
A tonneau is the rear portion of a vehicle, especially the passenger seating or luggage section at the back of an open car. In contemporary automotive use, it can also denote a covered rear compartment, most often in a pickup truck. Historically, the term referred to the box-shaped rear body of a light carriage. The word is more precise than generic terms such as “back” because it identifies a vehicle body section rather than the rear of the vehicle as a whole. Tonneau has a slightly technical sound but remains established in British and North American automotive usage. It is also useful for recognizing a word whose literal history is surprisingly concrete: it comes from French for a small barrel. The barrel image was eventually applied to vehicle bodywork, making “tonneau” a compact example of how an ordinary object can become a lasting piece of technical vocabulary.
nounThe rear body or passenger compartment of an automobile or similar vehicle, especially an open vehicle. The term can also denote a covered rear compartment, as on a pickup truck, and historically referred to the box-shaped rear body of a light carriage.
- The rear body or passenger compartment of an open automobile or similar vehicle.
- A rear compartment in a pickup truck or other vehicle, especially one covered by a hinged or removable cover.
- Historically, the box-shaped rear body of a light carriage.
"The roadster's spacious tonneau comfortably accommodated two passengers and their luggage."
"The roadster's spacious tonneau comfortably accommodated two passengers and their luggage."
"The driver secured the tonneau cover over the pickup's rear bed before the storm."
The plural tonneaus is standard; tonneaux is also an accepted variant.
"The collector compared the body shapes of three antique roadsters, paying particular attention to their tonneaus."
Tonneau literally means “small barrel,” a strikingly apt origin for the rear body that gave the word its automotive life.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does tonneau come from?
Tonneau was borrowed from French tonneau, literally a small barrel or tub and a diminutive of ton, meaning cask or tun. French ton continues Medieval Latin tonna, a cask. The barrel comparison was extended to the rear body of vehicles, and English subsequently used the word for carriage and automobile body sections and for covered rear vehicle compartments.
Related word forms
How tonneau is actually used
The term is standard in British and North American English and is especially common in automotive contexts. It identifies a specific rear body section or compartment rather than the vehicle's entire rear end.
Easily confused with tonneau
A tonneau is a vehicle body or compartment, whereas a tonne is a metric unit of weight equal to 1,000 kilograms.