The Collaborative International Dictionary of English v.0.48:

Glebous \Gleb"ous\, Gleby \Gleb"y\, a. [Cf. L. glaebosus
   cloddy.]
   Pertaining to the glebe; turfy; cloddy; fertile; fruitful.
   "Gleby land." --Prior.
   [1913 Webster]