blow-by

1. blow-by Noun. (automotive) in an w:Internal combustion engine|internal combustion engine, any burnt or unburnt matter escaping from the cylinder, past the (worn) rings on the piston, and into the crankcase.
internal combustion engine
1. Noun. A piston or a rotary heat engine directly powered by the products of intermittent combustion of a fuel.
2. Noun. A heat engine in which intermittent or the continuous burning of a fuel takes place inside a combustion chamber; the resulting pressurized gas acts directly on the engine to do useful work, such as a piston engine, gas turbine, jet engine or rocket.[http://www.google.com/url?sa=t&ct=res&cd=1&url=http%3A%2F%2Fwww.britannica.com%2Feb%2Farticle-9106036%2Finternal-combustion-engine&ei=ZdJqSMCnDo_o0gXitpynDA&usg=AFQjCNE6h_t0H7XJLKnUjudcNQjmgMeUdg&sig2=srdZ
cylinder
1. Noun. (geometry) A surface created by projecting a closed two-dimensional curve along an axis intersecting the plane of the curve.
2. Noun. (geometry) A solid figure bounded by a cylinder and two parallel planes intersecting the cylinder.
3. Noun. Any object in the form of a circular cylinder.
4. Noun. A cylindrical cavity or chamber in a mechanism, such as the counterpart to a piston found in a piston-driven engine.
5. Noun. A container in the form of a cylinder with rounded ends for storing pressurized gas.
6. Noun. An early form of phonograph recording, made on a wax cylinder.
7. Noun. The part of a revolver that contains chambers for the cartridges.
8. Noun. (computing) The corresponding tracks on a vertical arrangement of disks in a disk drive considered as a unit of data capacity.
rings
1. Noun. (plural of|ring)
2. Noun. (gymnastics) A gymnastics apparatus and discipline consisting of 2 rings suspended from a bar.
3. Verb. (en-third-person singular of|ring)
Piston
1. Proper noun. (surname)
piston
1. Noun. A solid disk or cylinder that fits inside a hollow cylinder, and moves under pressure (as in an engine) or displaces fluid (as in a pump)
2. Noun. (music) A valve device in some brass instruments for changing the pitch
crankcase
1. Noun. the part of an engine that contains the crankshaft