The upper side of a leaf is known as the adaxial surface.    From Wordnet, Princeton University. 

Inferred ancestral features include more than two whorls (or series) of tepals and stamens, stamens with protruding adaxial or lateral pollen sacs, several free, ascidiate carpels closed by secretion, extended stigma, extragynoecial compitum, and one or several ventral pendent ovule (s).    From Wordnik.com.  [A Disclaimer for Behe?] Reference

Botany Of or on the lower or inner surface of an organ that faces the axis; adaxial.    From Wordnik.com.  [Word of the Day] Reference

Typically, the stomata are more numerous over the abaxial (lower) epidermis than the (adaxial) upper epidermis.    From Wordnik.com.  [Wikibooks - Recent changes [en]] Reference

At the same time, water also condenses on the adjacent spore surface and a lens-shaped "adaxial drop" develops.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

Intact adaxial sheath epidermal cells were imaged with an Olympus FV1000 confocal microscope equipped with a 60×oil immersion lens.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

Initially, Buller's drop is separated from the adaxial drop by its position on a knob called the hilar appendix, but the expanding drops coalesce when their surfaces make contact.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

T. caries (Fig. 1a), the merger of Buller's drop with a prominent adaxial drop is associated with a much greater change in surface tension that powers the longer flight of the spore.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

In ferns and most flowering plants the mesophyll is divided into two layers: palisade layer of tightly packed, vertically elongated cells, one to two cells thick, directly beneath the adaxial epidermis.    From Wordnik.com.  [Wikibooks - Recent changes [en]] Reference

Most leaves show dorsoventral anatomy: the upper (adaxial) and lower (abaxial) surfaces have somewhat different construction and may serve different functions. transparent (epidermal cells lack chloroplasts) and coated on the outer side with a waxy cuticle that prevents water loss.    From Wordnik.com.  [Wikibooks - Recent changes [en]] Reference

Petiole 2-6 mm, puberulent and ± setose; leaf blade papery, oblong to oblong - lanceolate, 5-11 × 1. 5-3.5 cm; base cuneate; margin ciliate; apex obtuse and mucronate; abaxial surface densely gray-white-pubescent, yellow-brown setose along midrib; adaxial surface sparsely to densely puberulent when young.    From Wordnik.com.  [Find Me A Cure] Reference

A. tabescens, for example, the adaxial fluid on the adjacent spore surface does not form a prominent lens shape before discharge, and Buller's drop flips onto the spore and is carried as a discrete hemisphere during the launch (.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

1,600 cells in the front (abaxial) epidermis and about 2,800 in the back (adaxial) epidermis.    From Wordnik.com.  [PLoS Biology: New Articles] Reference

(Life Sciences & Allied Applications/Botany) of, relating to, or situated on the upper or inner side of a plant organ, esp a leaf, that is facing the axis ventral - 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" dorsal - belonging to or on or near the back or upper surface of an animal or organ or part; "the dorsal fin is the vertical fin on the back of a fish and certain marine mammals" ventral - nearest to or facing toward the axis of an organ or organism; "the upper side of a leaf is known as the adaxial surface".    From Wordnik.com.  [Word of the Day] Reference