Wiktionary
rock slam
n. (context Scientology English) An erratic slashing motion of an E-meter's needle, supposed to indicate evil intentions in the subject.
Usage examples of "rock slam".
She felt unyielding rock slam up into the Daimler's belly like a boxer taking a heavy body blow, and the back wheels crabbed over the pile of broken earth, the rubber tyres screeching as they sought purchase on the tumbled boulders.