The Collaborative International Dictionary of English v.0.48:
Hermes \Her"mes\, n. [L., fr. Gr. ?.]
   1. (Myth.) See Mercury.
      [1913 Webster]
   Note: Hermes Trismegistus [Gr. 'Ermh^s trisme`gistos, lit.,
         Hermes thrice greatest] was a late name of Hermes,
         especially as identified with the Egyptian god Thoth.
         He was the fabled inventor of astrology and alchemy.
         [1913 Webster]
   2. (Arch[ae]ology) Originally, a boundary stone dedicated to
      Hermes as the god of boundaries, and therefore bearing in
      some cases a head, or head and shoulders, placed upon a
      quadrangular pillar whose height is that of the body
      belonging to the head, sometimes having feet or other
      parts of the body sculptured upon it. These figures,
      though often representing Hermes, were used for other
      divinities, and even, in later times, for portraits of
      human beings. Called also herma. See Terminal statue,
      under Terminal. Hermetic
The Collaborative International Dictionary of English v.0.48:
Herma \Her"ma\, n.; pl. Herm[ae]. [L.]
   See Hermes,
   2.
      [1913 Webster]