To do nothing, to be idle.
To headbutt (from loaf of bread)
To be in catloaf position (for cats or other animals)
A block of bread after baking.
Any solid block of food, such as meat or sugar.
A solid block of soap, from which standard bar soap is cut.
Shortened from "loaf of bread", the brain or the head (mainly in the phrase use one's loaf).
To spend time sitting idly, not doing anything important.