Definition
To force someone to do something by putting them in a situation where they have no other choice; to control or extort someone by placing them in a position where they have no alternative.
The criminals attempted to hold the company to ransom by taking hostages.
The union threatened to hold the company to ransom with a strike if their demands were not met.
The opposition party used the parliamentary deadlock to hold the government to ransom in order to achieve their political goals.