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hyperdactylia

American  
[hahy-per-dak-til-ee-uh] / ˌhaɪ pər dækˈtɪl i ə /
Also hyperdactylism

noun

  1. the presence of extra fingers or toes.


Etymology

Origin of hyperdactylia

1900–05; hyper- + New Latin -dactylia -dactyly