nectar

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A sweet liquid that many plants secrete from specialized structures, often inside flowers, where it serves to attract pollinators such as certain insects and birds. Bees use nectar to make honey.
• noun Greek & Roman Mythology The drink of the gods.
• noun A beverage containing fruit juice or purée.
• noun A delicious or invigorating drink.

from The Century Dictionary.

• noun In classical mythology, the drink or wine of the Olympian gods, poured out for them by Hebe and Ganymede, the cupbearers of Zeus.
• noun Hence, any delicious and salubrious drink.
• noun In botany, the honey of a flower; the superfluous saccharine matter remaining after the stamens and pistils have consumed all that they require.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Myth. & Poetic) The drink of the gods (as ambrosia was their food); hence, any delicious or inspiring beverage.
• noun (Bot.) A sweetish secretion of blossoms from which bees make honey.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun fruit juice especially when undiluted
• noun (classical mythology) the food and drink of the gods; mortals who ate it became immortal
• noun a sweet liquid secretion that is attractive to pollinators