{"data":{"fields":"term_definition","term_definition":"<div class=\"definition\">Refers to a testing machine which is provided with a pivoted pinion spindle whereby the pinion shaft is permitted to move laterally in a horizontal plane either side of its theoretically correct position, but is forced by light spring pressure in the direction (side movement) to place the gears in metal-to-metal contact. As the gears are rolled slowly by hand, any irregularities will cause lateral displacement of the pinion axis, which is measured by a dial indicator or recorded on a strip recorder.<\/div>"}}