Word Study
tonneau
CIDE DICTIONARY
tonneau, n. [F.].
- In France, a light-wheeled vehicle with square or rounded body and rear entrance. [Webster 1913 Suppl.]
- Orig., the after part of the body with entrance at the rear (as in vehicle in def. 1); now, one with sides closing in the seat or seats and entered by a door usually at the side, also, the entire body of an automobile having such an after part. [Webster 1913 Suppl.]
- same as Tonne. [Webster 1913 Suppl.]
OXFORD DICTIONARY
tonneau, n. the part of a motor car occupied by the back seats, esp. in an open car.
Idiom
tonneau cover a removable flexible cover for the passenger seats in an open car, boat, etc., when they are not in use.
Etymology
F, lit. cask, tun
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