What is the function of egg in meatloaf?

Binding: Eggs help to bind the ingredients of meatloaf together, preventing it from falling apart during cooking.

Moisture: Eggs add moisture to meatloaf, which can help to keep it from drying out during baking.

Richness: Eggs add richness and flavor to meatloaf.

Leavening: Eggs can also act as a leavening agent, helping to make meatloaf light and fluffy.

Glaze: Some recipes call for brushing the top of the meatloaf with an egg wash before baking, which can help to create a golden brown crust.