A combination of Absinthe and Marijuana.

It is a portmanteau of the slang for Absinthe ("Green Fairy") and the slang for Marijuana ("Mary Jane").
I decided to follow up my delicious glass of absinthe with a few hits of marijuana. I lovingly refer to this concoction as Fairy Jane.

Fairy Jane is better than my typical Saturday night out that consists of excessive drinking of fairly decent alcohol, or only a few hits of pot.
by Death Swoon February 12, 2010
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