Don't have a cow意思
"Don't have a cow" is an American English idiom that means to not overreact or to calm down. It is a casual expression, often used humorously, to tell someone that their reaction to a situation is disproportionate to the circumstances. The phrase is believed to have originated in the 1960s and became popularized in the 1970s.
The origin of the phrase is somewhat unclear, but it is thought to be related to the idea of a cow being a large, somewhat clumsy animal. The expression may be suggesting that someone is acting like a bull in a china shop, causing chaos and destruction in a situation that doesn't warrant such a reaction.
Here's an example of how "don't have a cow" might be used in a conversation:
Person A: I can't believe I forgot to call Mom on her birthday! She's going to kill me! Person B: Calm down, don't have a cow. It's not the end of the world. Just call her and apologize.
In this example, Person B is using "don't have a cow" to tell Person A to relax and not to overreact to the situation.