The Collaborative International Dictionary of English v.0.48:

Melissa \Me*lis"sa\, n. [NL., fr. Gr. me`lissa a bee, honey.]
   (Bot.)
   A genus of labiate herbs, including the balm, or bee balm
   (Melissa officinalis).
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

beebalm \beebalm\, bee balm \bee balm\n.
   1. a perennial herb (Monarda fistulosa) of North America.
      [WordNet 1.5]

   2. a perennial aromatic herb of eastern North America
      (Monarda didyma) having variously colored tubular
      flowers in dense showy heads.

   Syn: bee balm, bergamot mint, oswego tea.
        [WordNet 1.5]

   3. a bushy perennial Old World mint, Melissa officinalis,
      having small white or yellowish flowers and fragrant
      lemon-flavored leaves; a garden escapee in northern Europe
      and North America.

   Syn: lemon balm, garden balm, sweet balm, bee balm, Melissa
        officinalis.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Melissa officinalis
    n 1: bushy perennial Old World mint having small white or
         yellowish flowers and fragrant lemon-flavored leaves; a
         garden escapee in northern Europe and North America [syn:
         lemon balm, garden balm, sweet balm, bee balm,
         beebalm, Melissa officinalis]