Hydrolock
Hydrolock (a shorthand notation for hydrostatic lock or hydraulic lock) is an abnormal condition of any device which is designed to compress a gas by mechanically restraining it caused by a liquid entering the device. In the case of a reciprocating internal combustion engine, a piston cannot complete its travel and mechanical failure may occur if a volume of liquid greater than the volume of the cylinder at its minimum (end of the piston's stroke) enters the cylinder, due to the incompressibility of liquids.