The Collaborative International Dictionary of English v.0.48:

Nectar \Nec"tar\, n. [L., fr. Gr. ?.]
   1. (Myth. & Poetic) The drink of the gods (as ambrosia was
      their food); hence, any delicious or inspiring beverage.
      [1913 Webster]

   2. (Bot.) A sweetish secretion of blossoms from which bees
      make honey.
      [1913 Webster]

WordNet (r) 3.0 (2006):

nectar
    n 1: a sweet liquid secretion that is attractive to pollinators
    2: fruit juice especially when undiluted
    3: (classical mythology) the food and drink of the gods; mortals
       who ate it became immortal [syn: ambrosia, nectar]

The Devil's Dictionary (1881-1906):

NECTAR, n.  A drink served at banquets of the Olympian deities.  The
secret of its preparation is lost, but the modern Kentuckians believe
that they come pretty near to a knowledge of its chief ingredient.

    Juno drank a cup of nectar,
    But the draught did not affect her.
    Juno drank a cup of rye --
    Then she bad herself good-bye.
                                                                  J.G.