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arachnodactyly

n. a condition in which the fingers and hands are abnormally long and slender

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Arachnodactyly

Arachnodactyly ("spider fingers") or achromachia is a condition in which the fingers and toes are abnormally long and slender, in comparison to the palm of the hand and arch of the foot. Also, the individual's thumbs tend to also be pulled inwards towards the palm. It can be present at birth or develop in later life..