Definitions for "blowby"
the leakage of gases from the combustion cylinder of an internal combustion engine between the piston and cylinder wall into the crankcase.
Combustion gases, composed of water vapor and unburned fuel, that leak past the piston rings into the crankcase during normal engine operation. These gases are removed by the PCV system to prevent the buildup of harmful acids in the crankcase.
1. The technique sometimes used for recycling concentrate back to the feed.