hold out on (someone or something)
To keep something from someone or something else, especially information or money. Are you holding out on me? Do you know more details about the merger than you're letting on? Someone needs to chip in three more bucks and I'll have enough to cover the bill. Who's holding out on me?
hold (something) out on (someone or something)
to keep news or something of value from someone or a group. What's going on? Are you holding something out on me? Don't hold out on the city council. They have ways of finding out everything.
hold out on (someone)
To withhold something from: Don't hold out on me; start telling the truth.