that's what (someone) thinks(redirected from that's what someone thinks)
that's what (someone) thinks
Someone is totally wrong about what they think. A: "Bob said he's planning on taking his vacation next week." B: "That's what he thinks—we need everyone here to get this project finished before the deadline!" A: "I need you to stay home this Saturday to look after your sister." B: "That's what you think! I already bought tickets to the concert on Saturday."