Adjectives

(a)ventraltoward 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”
(a)adaxial, ventralnearest to or facing toward the axis of an organ or organism“the upper side of a leaf is known as the adaxial surface”