/hang"kee pang"kee/ , n. Informal.
1. unethical behavior; deceit: When the bank teller bought an expensive car and house, they suspected there might be some hanky-panky going on.
2. illicit sexual relations.
Also, hankey-pankey, hanky pank .
[ 1835-45; rhyming compound; cf. initial h, p of HIGGLEDY-PIGGLEDY, HOCUS-POCUS, HODGE-PODGE, etc. ]