I remember having learned it from the TV. But I can't remember what it is now.
It's a verb synonym of drug or poison. It means someone slips some drug into someone's food or water. The drug may be just some sedatives.
Learn English – What’s the word for drugging someone
single-word-requestssynonyms
Best Answer
I think in relation to alcohol, you may be thinking of "Slip a Mickey" or "Mick" or "Roofie".
http://en.wikipedia.org/wiki/Mickey_Finn_%28drugs%29
http://www.urbandictionary.com/define.php?term=slipped%20a%20mickey
https://answers.yahoo.com/question/index?qid=20091116141136AAOITR5