What does satiation mean?

When you are in ketosis you are using primarily FAT for energy.  If you are trying to lose weight then you want a lot of that to come from your body fat – but can you just eat almost NO fat and lose weight fast? Not really.  Humans are only able to draw down about 31.5 Calories per day per pound of body fat (Show me the science) – so there is a limit. You need to eat fat when you are hungry or your metabolic rate will be slowed to compensate.  

When you first start adapting to fueling your body on fat you may not be as efficient at mobilizing energy stored in body fat to the mitochondria of tissue that needs to use energy.  So in the early days you are probably going to still eat 3 meals a day and most of that will be fatty meats, eggs, butter, and the like.  If you are hungry, really hungry, then your body is telling you that it is running out of energy. Satiation is the point where you are no longer hungry.