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Illustration showing two types of human hand grips: a power grip holding a stick with the whole hand and a precision grip holding a small object between the thumb and fingertips.
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Superficial arteries and veins of face and scalp, cardiovascular system, human anatomy, (Netter replacement project - SSC)
The Human Body
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Also called:
pollex
Related Topics:
hand
digit
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thumb

anatomy
Also known as: pollex
Written and fact-checked by
Britannica Editors
Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree....
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History

thumb, short, thick first digit of the human hand and of the lower-primate hand and foot. It differs from other digits in having only two phalanges (tubular bones of the fingers and toes). The thumb also differs in having much freedom of movement and being opposable to tips of other digits. The corresponding first digit (most medial digit) in other vertebrates is also called the thumb, especially if it has some manipulative or special ability (e.g., in the raccoon and the bat).