1. To use something absorbent to clean the inside of something. A noun or pronoun can be used between "swab" and "out." Did you hear me? I said go clean your room! Do you need to swab your ears out? The doctor carefully swabbed out the wound and then rinsed it with a saline solution.

2. To use something absorbent to clean dirt or other contaminants out of something. A noun or pronoun can be used between "swab" and "out." It always makes me gag to see him swabbing wax out of his ears like that. Make sure you carefully swab out all the dirt before you apply the bandage.