Mickey Finn
noun
Mick·ey Finn ˌmi-kē-ˈfin 
: a drink of liquor doctored with a purgative or a drug
Word History
Etymology
probably from Mickey (Michael) Finn flourished 1903 American saloon keeper who allegedly drugged his customers
First Known Use
1918, in the meaning defined above
Medical Definition
Mickey Finn
noun
ˌmik-ē-ˈfin
: a drink of liquor doctored with a purgative or a drug