A bid that deliberately and substantially misstates the strength and / or distribution of a hand. So long as the bid is as much of a surprise to your partner as the opponents, psychic bids are a legitimate part of the game.
For example:
![](https://bernardmageebridge.com/wp-content/uploads/2021/11/image-226.png)
Knowing that North-South certainly have a game on and possibly a slam, West feigns a show of strength by asking for aces.