To resolutely avoid something because it is perceived as highly undesirable or dangerous.
"I hate crowds and avoid it like poison ivy, especially during flu season."
Manson's law of avoidance says that, the more something threatens your identity, the more you will avoid it and I (Manson) bring this up in terms of what are the pieces of information that we protect ourselves from because ultimately, like grasping onto some sense of certainty, it's a means of protecting our ego from perceived threats and so, Manson's law basically says that, the more threatening something is, the more we will become certain in things that will help us avoid dealing with that truth.
An extension of Manson's law of avoidance is that, we should define ourselves as loosely and ambiguously as possible because the less defined ourself is, the less we need to cling to defense mechanisms or faulty ideas to protect ourselves. This is fundamentally a Buddhist idea, the idea of no self, if there is no such thing as self, then there's nothing to protect and there's nothing that you need to be certain about in the first place.
Someone who is so morbidly obese with no intent of changing, that they do everything in their power to avoid losing weight, including eating salads.
Person 1: Hey, do you see that Salad Avoider over there?
Person 2: Yeah, he has more chins than Chinatown.