Short for "
shenanigans".
When dining with a group of friends, it is perfectly acceptable to
tamper with or "shen" their food, drink or personal property if they leave the table at any time
The only way to counter a shen is for a person to declar "No
shens." or "No shenanigans." when leaving the table temporarily.
"Bob
got up to go to the bathroom and we totally shenned him! We
hid sugar packets in his
coat pocket and mixed salt in with his Coke."