Since flip means to turn over and lid means a movable cover, how in the world does “flip your lid” mean to become very angry? The best way to even start to explain how this idiom came to mean something completely different is by providing an analogy — take a teapot that has a lid with an air hole, and when the water boils inside the teapot, the lid starts to whistle, making it sound angry (which we really know means that the water has boiled, is hot). And doesn’t “hot” in this sense of flipping your lid mean becoming angry .
“I’m so hot (angry) I could flip my lid (blow some steam).”
If I’m talking about a topic to someone, and that person is not liking the topic and becoming irate, angry, he just might “flip his lid”, lose self-control because of the topic.
Ah, a bit of an explanation.
There are other idioms, everyday phrases in America, that mean the same. Some we hear more than others, but they are basically the same. Take “flip out.” We are not turning anything over and putting it outside, but when we “flip out” it means that we are losing emotional control, acting wildly, or losing our temper. We do not “flip out” when something good happens, like the Chicago Cubs winning to go to the World Series, but we do flip out when negative happens, like when that promotion at work went to someone else who is less deserving. We could “flip out”, act wildly, or simply lose our temper.
Sometimes it could mean “going crazy” but flip out is only used in this case when a person really goes crazy, not just a temporary action of acting wildly, but the kind of wildness when a person has a psychotic break.
My all time favorite is “lose it” — I use this to have many meanings. You could “lose it” when I view you as becoming irrationally angry, and I walk away. Or, maybe you have said something to me that will make me lose my temper, and I will say “I better leave before I lose it”, lose my temper. But the best one is simply when I mean I’m going to lose my mind — like when the Cubs won enough games to go to the World Series, I could lose my mind, “lose it” because of elation. Here, “lose it” has both positive and negative influences, depending on what is happening.
So, I hope this helps you understand something about that teapot, that anger, that lid that is flipping.
Then again, maybe I need to simply put a lid on it (stop it) before I over explain.