To force someone to do something, often by using tricks or lies.
This meaning can make people think of being taken away from home or being treated unfairly.
Examples:
The pirates shanghai the sailor and take him on their ship.
I won't let anyone shanghai me into doing something I don't want to do.
She was shanghaied into working for the bad guys.
The cat shanghaied the mouse into helping him get the cheese.
The aliens shanghaied the cows and took them to their planet.
He was shanghaied into going to bed early.