To remove something (off of someone or something else) with vigorous scrubbing, especially by using a very abrasive brush or cleaning pad. A noun or pronoun can be used between "scour" and "off." You'll need to scour off the dirt before you start boiling the potatoes. I spent the whole day scouring rust off the fence around our property.
scour something off (of) somethingand scour something off
to clean something off something else by scouring. (Of is usually retained before pronouns.) See if you can scour the rust off the cookie sheet. I will scour off the rust with steel wool.