The medical term for the big toe, the innermost and largest of the five toes on each foot.
From Latin hallux of uncertain origin, possibly related to a root meaning 'to leap' or an older word for toe. It became the anatomical standard in medical Latin.
Your hallux is the only toe that doesn't have a 'cousin' on the other side in some animals—humans evolved an opposable big toe specifically for walking upright, making it the key innovation that freed our hands to use tools.
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