The top portion of a compression valve assembly, it holds the valve in place as it is tightened against the valve seat at the other end of the assembly
Anything resembling a bonnet in shape or use A small defense work at a salient angle; or a part of a parapet elevated to screen the other part from enfilade fire
The bonnet of a car is the metal cover over the engine at the front. When I eventually stopped and lifted the bonnet, the noise seemed to be coming from the alternator
protective covering consisting of a metal part that covers the engine; "there are powerful engines under the hoods of new cars"; "the mechanic removed the cowling in order to repair the plane's engine"