Educational Content: This article is for informational purposes only and does not constitute medical advice. Always consult a healthcare provider for diagnosis and treatment.

Definition of Thumb

Medically reviewed by Min Clinic Staff | Updated: January 2026

Thumb: The short thick finger situated at an angle to the other fingers so it can be opposed to the them, making it possible to pick up and hold things. The thumb is analogous in position to the big toe (the great toe) and similarly has only two phalanges (all the other digits have three).