Source : Webster's Revised Unabridged Dictionary (1913)

Glabrous \Gla"brous\, a. [L. glaber; cf. Gr. ? hollow, smooth, ?
   to hollow.]
   Smooth; having a surface without hairs or any unevenness.

Source : WordNet®

glabrous
     adj : having no hair or similar growth; smooth; "glabrous stems";
           "glabrous leaves"; "a glabrous scalp"