Any substance with Oneirogenic effects; producing twilight sleep, hypnogaugia, lucid dreaming, intense visions, or euphoria during repose, but which have little or no effect on an alert wakeful consciousness.
"That stuff I ordered online didn't do much for me until I fell asleep-- and man was it ever sleepadelic!"
When some resigns or retires from a job, they are on "eternity leave". This can also refer to someone who has passed away, especially someone who worked somewhere for a long time, retired/resigned, then passed away later.
Oh I'm sorry, you didn't know that Kelly is on eternity leave? She resigned and moved to Hawaii!
With regrets I would like to inform you that my boss is officially on eternity leave. I will never see or hear them again. Ever.