polydactyly

/ˌpɑlɪˈdæktəli/
noun
  1. A condition in which a person or animal is born with more than the usual number of fingers or toes.
    • Polydactyly is often a harmless genetic trait that does not affect a person's health.
    • The kitten was born with polydactyly, giving it seven toes on each front paw.
    • The doctor explained that polydactyly can be surgically corrected if needed.