| compression |
the reduction in volume and increase in pressure of air or air mixed with fuel in the cylinder of an internal combustion engine prior to ignition, or the engine cycle in which this process takes place. [1/3 definitions] |
| compression ratio |
in an internal-combustion engine, the ratio of the largest to the smallest volume of a cylinder measured at the top and bottom of the piston stroke. |
| cowling |
the removable metal housing of an aircraft engine, often designed as part of the fuselage. |
| crank |
to turn (a shaft) by use of a mechanical crank, or start (an engine) by use of a crank or other device. [1/6 definitions] |
| cylinder |
in a pump or engine, the cylinder-shaped chamber in which a piston moves. [1/5 definitions] |
| cylinder head |
of the cylinder in an internal-combustion engine, the closed, often detachable end opposite to that from which the piston or connecting rod projects. |
| dead center |
the maximum or minimum extension of a crank and connecting rod in a reciprocating engine, in which both are in a straight line and the connecting rod cannot turn the crank. [1/2 definitions] |
| diesel |
shortened form of "diesel engine," a type of internal-combustion engine that burns fuel oil which is ignited by being sprayed into a chamber in which highly compressed air, rather than an electric spark, provides the heat. [3 definitions] |
| diesel engine |
a type of internal-combustion engine that burns fuel oil which is ignited by being sprayed into a chamber in which highly compressed air, rather than an electric spark, provides the heat. |
| distributor |
an electrical device in an internal combustion engine that transmits current in proper sequence to the spark plugs. [1/2 definitions] |
| dolly |
a small train engine used in a railway yard, quarry, or the like. [1/6 definitions] |
| donkey |
of an engine, pump, or the like, auxiliary. [1/3 definitions] |
| driving wheel |
a wheel that transmits power from an engine, either to other wheels, or into propulsive effort, as on a locomotive engine. |
| dune buggy |
a lightweight car, usu. without doors or windows, that has a rear-engine chassis and oversized tires that make driving over sand dunes easier. |
| engineer |
one who runs an engine or locomotive. [1/5 definitions] |
| engineless |
combined form of engine. |
| ethyl |
a fluid containing tetraethyl lead and other substances, used in gasoline to reduce engine knock. [1/3 definitions] |
| exhaust |
to pass out as waste, as the fumes of an engine. [3/11 definitions] |
| external-combustion engine |
an engine in which the combustion of fuel occurs outside the cylinder or turbine, as in a steam engine. |
| fan belt |
in an automobile engine, a rubber belt stretched firmly around the crankshaft, which transfers torque to another shaft located on the cooling fan. |
| fanjet |
a jet engine that uses an impeller fan to draw in more air than is needed for fuel combustion, the excess being mixed with the products of the combustion to form an exhaust jet that provides extra thrust; turbofan. [2 definitions] |