1. Thumb
Pollex is the medical term for Thumb.
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The word "pollex" is the Latin medical term for the thumb.
The thumb, also called the pollex, is the first, first digit of the human hand and of the lower hand and feet.
It differs from other digits in that it has only two phalanges. The thumb also differs from having greater freedom of movement and opposing the tips of other digits. The first digit corresponding to other vertebrates is also called a thumb, especially if it has a certain trick or special ability.