A disk harrow being pulled by a tractor.
disk harrow definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
a harrow with sharp, revolving circular blades, used to break up soil for sowing
disk harrow definition by American Heritage Dictionary
or disc harrownoun
A harrow equipped with a series of sharp metal disks set on edge or at an angle on one or more axles.