waving the rod—A procedure used to make sure that a leveling rod is plumb when a measurement is taken. The procedure consists of slowly tilting the rod toward and away from the instrument, while the person as the instrument observes the rod readings. The rod is plumb when the reading is at its minimum.

–

Source: NSPS “Definitions of Surveying and Related Terms“, used with permission.

Part of LearnCST’s exam text bundle.