milium

/ˈmɪliəm/
noun
  1. A small, white, hard bump on the skin, usually on the face, caused by trapped keratin.
    • Milium cysts are common in newborns and usually harmless.
    • The baby had a tiny milium on her nose that went away on its own.
    • My dermatologist said the white bump under my eye is a milium, not a pimple.