cotton swab

US /ˈkɑː.tən swɑːb/
UK /ˈkɑː.tən swɑːb/
"cotton swab" picture
1.

a small wad of cotton on a short stick, used for cleaning or applying medication

:
She used a cotton swab to clean the baby's ears.
Apply the antiseptic with a sterile cotton swab.