/tu noh"/ , n. , pl. tonneaus, tonneaux /-nohz"/ .
1. a rear part or compartment of an automobile body, containing seats for passengers.
2. a complete automobile body having such a rear part.
3. a waterproof cover, generally of canvas or vinyl, that can be fastened over the cockpit of a roadster or convertible to protect the interior.
[ 1900-05; tonel . See TUNNEL ]