abaxial
1. [ adjective ] situated away from the axis of any body or part
Synonyms: abaxile
Related terms: axis axial
2. [ adjective ] (biology) facing away from the axis of an organ or organism
Synonyms: dorsal
Examples:

"the abaxial surface of a leaf is the underside or side facing away from the stem"

Related terms: adaxial biology
Similar spelling:   abaxially
  abaxile
  abyssal