noun
: either of two loops of blood vessels in the palm of the hand:
a. : a deep arch that is formed by the continuation of the radial artery and a branch of the ulnar artery and supplies principally the deep muscles of the hand, thumb, and index finger
b. : a superficial arch that is the continuation of the ulnar artery which anastomoses with a branch derived from the radial artery, its branches mostly going to the fingers