cotton bud
noun /ˈkɒtn bʌd/
  /ˈkɑːtn bʌd/
 (British English) (also cotton swab North American English, Q-tip™ North American English, British English)
- a small stick with cotton wool at each end, used for cleaning inside the ears, etc.(用于清洁耳朵内部等的)棉签