plagiocephaly

/ˌpleɪdʒioʊˈsɛfəli/
noun
  1. A condition in which a baby's head is flattened on one side, often from lying in the same position for too long.
    • Many parents worry about plagiocephaly, but helmets are only needed in severe cases.
    • Plagiocephaly is usually not dangerous and can be corrected with simple repositioning techniques.
    • The pediatrician diagnosed the infant with mild plagiocephaly and recommended more tummy time.