ventral

英 ['ventr(ə)l] 美['vɛntrəl]

1. toward or on or near the belly (front of a primate or lower surface of a lower animal);: "the ventral aspect of the human body"; "the liver is somewhat ventral in position"; "ventral (or pelvic) fins correspond to the hind limbs of a quadruped"

2. nearest to or facing toward the axis of an organ or organism;: "the upper side of a leaf is known as the adaxial surface"