Swab/swɑːb/ Definition 1 of 3Pro Tip 1/3Medical Context Used primarily in medical settings to collect samples or apply treatments. The doctor used a swab to collect cells for the lab test. Pro Tip 2/3Not for Ears Although commonly used, medical advice suggests not using swabs to clean ears. Use a washcloth instead of a swab to clean your ears safely. Pro Tip 3/3Disposable Item Swabs are often disposable and should be discarded after one use to prevent contamination. After cleaning the cut, she threw the swab away.