Blowby

Gases created during combustion that leak past the piston rings and are removed from the crankcase via the PCV system.
Found on http://www.expertasig.ro/dictionar/car_terms.php

blowby

leakage of combustion gases between a piston and the cylinder wall into the crankcase in an automobile
Found on http://www.encyclo.co.uk/local/21121
No exact match found