scavenging

noun

Street-cleaning; removal of filth.

noun

The process of cleansing, especially in internal-combustion motors. See scavenge, 2.

noun

Act or process of expelling the exhaust gases from the cylinder by some special means, as, in many four-cycle engines, by utilizing the momentum of the exhaust gases in a long exhaust pipe.

verb

Present participle of scavenge.