Laugh somebody/something out of court
Definition 1 of 1
Pro Tip 1/3Negative Connotation
The phrase implies strong disapproval and is used to express that an idea is absurd. 
Her plan to turn the office into a zoo was laughed out of court.
Pro Tip 2/3Not Literal
It doesn't involve actual laughter or a court; it's a figurative way to say an idea was dismissed. 
His idea about flying cars was laughed out of court.
Pro Tip 3/3Informal Context
Best used in casual conversations or writing, not in formal contexts. 
The artist's unusual design was quickly laughed out of court.